Microbial fuel cell (MFC) is a green innovative technology that can be employed for nutrient removal/recovery as well as for energy production from wastewater. This paper summarizes the recent advances in the use of MFCs for nutrient removal/recovery. Different configurations of MFCs used for nutrient removal are first described. Different types of nutrient removal/recovery mechanisms such as precipitation, biological uptake by microalgae, nitrification, denitrification and ammonia stripping occurring in MFCs are discussed. Recovery of nutrients as struvite or cattiite by precipitation, as microalgal biomass and as ammonium salts are common. This review shows that while higher nutrient removal/recovery is possible with MFCs and their modifications compared to other techniques as indicated by many laboratory studies, field-scale studies and optimization of operational parameters are needed to develop efficient MFCs for nutrient removal and recovery and electricity generation from different types of wastewaters.

  • Several different configurations of MFCs are available for nutrient removal/recovery.

  • In MFCs nutrients are removed by a number of different mechanisms.

  • Nutrient can be recovered from a variety of wastewaters with MFCs.

  • Optimization of operating parameters and more field scale studies are required.

Graphical Abstract

Graphical Abstract
Graphical Abstract

The human population is struggling hard to meet their energy, freshwater and food requirements, and the water-energy-food nexus has now become an important topic of discussion (Wicaksono et al. 2017). The world is facing a serious energy crisis as the supply of conventional energy sources are not adequate to meet the needs of the entire human population. The increased use of conventional energy resources results in the emission of greenhouse gases causing climatic changes. Therefore, attempts to develop renewable energy resources and to reduce carbon footprint have gained momentum in recent years (Gielen et al. 2019). Similarly, the water crisis is another major problem that is faced by human beings. Wastewater treatment and reuse can rejuvenate the depleting water resources. However, most of the conventional wastewater treatment plants (WWTPs) are energy-consuming facilities that employ energy-intensive techniques (Tao & Chengwen 2012; Negi & Chandel 2021). It has been reported that the consumption of electrical energy in WWTPs in developed countries is about 3–5% of total electricity demand (Ye et al. 2019a). Wastewater can be considered as a renewable resource of water, energy and nutrients (Huang et al. 2011; Do et al. 2018). These nutrients recovered from wastewater can be used as a source to enhance agricultural production, thus reducing wastewater treatment costs (Yetilmezsoy et al. 2017; Ye et al. 2020b). Treating wastewater and recovering resources and energy can be adopted as a sustainable model in this scenario (Mohammed & Ismail 2018).

Wastewater can be treated using a variety of biological, physiochemical and membrane processes. Even though anaerobic technologies such as up-flow anaerobic sludge blanket can generate electricity by utilizing the methane produced during the process, their conversion efficiency is very low. A microbial fuel cell (MFC) is a system that uses electrodes and an ion exchange membrane (IEM) to generate electricity by utilizing the electrons produced during the metabolic activities of microorganisms. MFCs can be implemented in WWTPs simultaneously to treat the water and to generate electricity, which can solve water crisis and reduce the consumption of energy for wastewater treatment. During the oxidation of organic matter in the anode chamber of an MFC, electrons are transferred to the anode by an extracellular electron transfer mechanism in microorganisms (Sharma et al. 2021). Thus, MFC can be a suitable method of treatment where there is a power supply shortage. Wastewater can be added as a substrate in the anode chamber where microbial degradation and electron generation take place. Further, use of microalgae in the cathode chamber will help in CO2 sequestration, harvesting value-added products, and reducing the aeration cost in the cathode chamber (Wang et al. 2010). MFCs have been investigated for organic matter removal, removal and recovery of heavy metals and nutrients, sulphide removal and dye removal from various types of wastewaters (Yadav et al. 2012; Varanasi et al. 2015; Chen et al. 2019; Ye et al. 2019c; Singh & Kaushik 2021).

The increase in the population has resulted in an increased demand for food production, which in turn increased the demand for constant fertilizer supply (Sun et al. 2018; Patel et al. 2020). Phosphate is a non-renewable resource that is mainly derived from phosphate-based rocks that can only serve the market demand for the next 50–100 years, while ammonium is commercially produced by energy-intensive Haber–Bosch process (Ye et al. 2019c). Elevated levels of nitrogen and phosphorus are present in different types of wastewaters including municipal wastewater, swine wastewater, dairy wastewater, beverage wastewater, and coke wastewater (Kumar & Pal 2015). The higher concentrations of nitrogen and phosphorus in the aquatic environment can cause eutrophication and related problems (Yetilmezsoy et al. 2017). As phosphate and nitrogen are essential for the growth of food crops, recovering them from wastewater has a crucial economic and environmental impact and is a sustainable approach (Santos & Pires 2018). Chemical processes like precipitation and adsorption, biological uptake by living organisms and membrane systems are generally used for nutrient recovery from wastewater (Ye et al. 2020b).

Phosphate recovery from sludge formed from biological treatment is banned in several countries because recovered phosphate may contain pathogens and heavy metals (Ye et al. 2020a). Magnesium ammonium phosphate, also known as struvite is extensively used as a fertilizer in soil of low pH (Tao et al. 2015). Struvite recovery from wastewater by conventional precipitation method requires additional chemicals that increases the cost, while recovery by adsorption process requires desorption, which results in additional complexity and cost (Ye et al. 2020a). If phosphate alone is present, it can be precipitated by the addition of magnesium as cattiite (Hirooka & Ichihashi 2013). Ammonia can be recovered by air stripping and adsorption of volatile ammonia into acid solutions (Ye et al. 2018). Membrane technologies such as forward osmosis, membrane distillation, and electrodialysis are also being investigated for nutrient recovery (Ye et al. 2020a).

MFCs are now considered a promising technology to recover nutrients from wastewater along with the generation of electricity (Al-Mamun et al. 2017; Mukherjee et al. 2021). Applying aeration in cathode chambers is considered beneficial as it increases oxygen availability in the cathode chamber, leading to more hydroxyl production resulting in an alkaline pH, which helps in precipitation of struvite without the addition of chemicals (Ye et al. 2019c). Phosphate is partly removed by microbial absorption during their growth, and ammonium accumulated in the cathode chamber by diffusion caused by concentration gradients and migration by current field generation is precipitated along with phosphate (Ye et al. 2019c). Therefore, MFC can be regarded as a feasible approach for nutrient removal and can simultaneously convert the energy stored in chemical bonds of organic compounds to electricity (Tao et al. 2015). The microalgal-based photosynthetic MFCs are also getting increased attention as they can assimilate nutrients into algal biomass, which can be used for downstream biodiesel production, CO2 sequestration, and the recovery of other value-added products (Wang et al. 2019a; Arun et al. 2020). Oxygen produced by these microalgae acts as an electron acceptor in the cathode chamber and saves the cost of mechanical aeration (Arun et al. 2020).

The application of MFCs over other technologies has advantages such as lower sludge production compared to other aerobic and anaerobic technologies, and direct generation of electricity by providing an external circuit (Asai et al. 2017). Lower power density and higher operating costs are the major constraints that limit its application on a larger scale (He et al. 2017). Aeration cost in the cathodic compartment is a major issue that needs to be solved. Integration of MFCs with various other existing techniques may be a suitable approach to overcome these drawbacks. For example, decolorization of about 98% was reported by a novel MFCs coupled with a peroxicoagulation system (Jayashree et al. 2019). The energy generated from MFCs can make them a neutral or positive energy system (Ye et al. 2019c). The study conducted by Rahimnejad et al. (2012) demonstrated that stack arrangement of MFC was able to produce current required for 10 LED lamps and a digital clock. The scaled-up models can produce more current, which may reduce the energy required for aeration in the case of dual-chamber MFCs. In hybrid systems, MFCs have been explored widely as biosensors for in situ detection of BOD, metals and toxicity (Tan et al. 2021).

Some studies have been reported in the literature in recent years on the use of different configurations of MFCs for nutrient removal from wastewater. Although a few review papers have been published on the application of MFCs for wastewater treatment (He et al. 2017; Saravanan et al. 2021; Verma et al. 2021) and nutrient recovery (Kelly & He 2014; Paucar & Sato 2021), a review report focusing exclusively on nutrient removal using MFCs and their modifications is missing in the literature. This review focuses on nutrient removal and recovery using the emerging technology of MFCs. The paper first discusses the different configurations available for MFCs. Mechanisms of nitrogen and phosphorus removal in MFCs are then described. In an MFC, nutrient removal is affected by different parameters and these parameters are discussed next. Finally, challenges of this technology for nutrient removal and the future research needs are presented.

MFCs are bio-electrochemical systems in which the microbes transfer electrons produced in the anode chamber by oxidizing the organic substrate to the anode via an extracellular electron transfer mechanism generating electron flow through the external circuit, which is utilized to reduce oxygen to water in the cathode chamber (Zhang et al. 2014; Jaiswal et al. 2020). According to the application and arrangement of the components, there are different types of MFCs and these are discussed in this section.

Components of MFC

In general, MFCs consist of an anode and a cathode in one chamber or in separate chambers. Usually, an IEM is used to separate the two chambers (Huang et al. 2011; Zinadini et al. 2017). A schematic diagram of a dual-chamber MFC is presented in Figure 1.

Figure 1

Components of a dual-chamber microbial fuel cell.

Figure 1

Components of a dual-chamber microbial fuel cell.

Close modal
An anode chamber is a critical component of MFCs where oxidation of the organic compound takes place along with electron transfer from microbial cells to the anode electrode (Ieropoulos et al. 2005). Therefore, this chamber can be described as the heart of the MFC (Jaiswal et al. 2020). The anode chamber consists of an anode substrate, electrodes, and microbial culture. Organic matter is mainly removed in this chamber along with electricity generation, sulphate reduction, fermentation and methanogenesis (Wang et al. 2019a). The chemical reaction that takes place for a simple organic molecule containing carbon, hydrogen and oxygen is given below:
formula

The wastewater is added to the anodic chamber as a substrate, which is degraded by the microorganisms to simpler molecules. The electrons produced by these microorganisms are then flowed through an anode electrode to cathode generating electricity (Huang et al. 2011). In the early development stage of MFC, mediators were used in the anode chamber where bacterial species do not readily release electrons, but now this has become outdated following the discovery of electroactive bacteria (Ieropoulos et al. 2005; Ieropoulos et al. 2008). Redox mediators help in transferring electrons from within the microbial cell to electrodes. They can be either internally produced or externally applied. Generally, non-metallic materials, such as graphite rods, carbon paper, and carbon cloth, are used as the anode. Materials having characteristics such as low cost, high stability, high conductivity, low resistance and biocompatibility are generally considered for use as electrodes (Kusmayadi et al. 2020). Therefore, anode material, substrate characteristics, microbial species, and the electron transfer mechanism to the anode are the main factors that influence the overall efficiency of the system.

The electrons that are transferred from the anode are received by an electrode in the cathode chamber and the electron is taken by the electron acceptor in the cathode chamber completing the electron cycle. The cathode chamber acts as proton/cation receiver in a dual-chamber MFC (Jaiswal et al. 2020). The general reaction that occurs in cathode is given below:
formula

External aeration or an aqueous solution containing dissolved oxygen or any other electron acceptor is generally provided in the cathode chamber. In a single-chamber MFC, the air cathode acts as an electron acceptor. Carbon cloth, graphite fiber brush, and a mesh of carbon or stainless steel can be used as cathode. Cathode electrodes are usually coated with platinum or other catalyst to improve the oxygen reduction reaction (Mustakeem 2015).

A conventional dual-chambered MFC has two compartments that are separated by an IEM. A cation exchange membrane (CEM) (also known as a proton exchange membrane (PEM)) is used as an IEM. The CEM facilitates the transfer of protons and cations at high concentrations from anode chamber to cathode chamber, which helps nutrient recovery through precipitation (Rozendal et al. 2008; Ye et al. 2019c). Chen et al. (2015) has proposed the use of both anode exchange membrane (AEM) and CEM to recover nutrients in multistage operations. The most commonly used material in laboratory-scale studies is Nafion 117 membrane. An efficient membrane should not transfer oxygen from the cathode to the anode chamber and it should transfer protons very effectively (Jayashree et al. 2019). The IEM alone constitutes approximately 60% of the overall cost of the MFC systems in field-scale applications (Ge & He 2016).

Types of MFCs

Dual-chamber MFC, single-chamber MFC, up-flow MFC and stacked-type MFCs are some of the different types of popular MFCs used in laboratory-scale applications for nutrient removal. Schematics of these types of MFCs are presented in Figure 2.

Figure 2

Schematic representation of different types of MFCs. (a) Dual-chamber MFC. (b) Single-chamber MFC. (c) Up-flow MFC. (d) Stacked MFC.

Figure 2

Schematic representation of different types of MFCs. (a) Dual-chamber MFC. (b) Single-chamber MFC. (c) Up-flow MFC. (d) Stacked MFC.

Close modal

Dual-chamber MFC

This is the simplest form of MFC with anode and cathode chambers separated by an IEM. In some cases, anode effluent is used as an influent for the cathode chamber to increase efficiency and to further treatment (Don & Babel 2021). Dual-chamber MFCs working based on pH static control by adding a base to the anode chamber and an acid to the cathode chamber has also been reported by a few authors (Cord-Ruwisch et al. 2011).

Single-chamber MFC

The MFC system, which consists of only one chamber that has both cathode and anode, is known as a single-chamber MFC. The single-chamber MFC provides a simple and economic design (Kumar et al. 2017). In most cases, one side of the cathode faces towards the separator and the other side to the atmosphere. The cathode facing the liquid side requires a catalyst, binder material, and cloth separators for proper functioning (Ichihashi & Hirooka 2012; Hirooka & Ichihashi 2013). This configuration has many advantages over a dual-chamber system. The overall volume of the system can be decreased and the cost of air sparging in the cathode chamber is eliminated. The lack of a PEM between anode and cathode can increase oxygen diffusion, but this can reduce the cost of construction. The formation of an aerobic biofilm on the cathode surface can reduce the oxygen diffusion to a certain extent (Liu et al. 2005).

Up-flow MFC

In this type of arrangement, the anode is at the bottom, and the cathode is at the top, and the substrate is supplied from the bottom of the system towards the upper portion or separately to each chamber. Both portions may be separated by glass wool or glass bead layers as in an integrated constructed wetland–MFC system or by an IEM as in a dual–chamber MFC (He et al. 2006; Ma et al. 2016). The main advantage of this type of MFCs is that they can be scaled up easily compared to other models with emphasis on wastewater treatment than power generation (Kumar et al. 2017). A study conducted for the treatment of produced water from an oil and gas industry with up-flow MFC documented a best power density of 227 mW/m2 (Cabrera et al. 2022).

Stacked MFC

MFCs can be arranged either in series or in parallel to increase the efficiency of the system (Kumar et al. 2017; Tan et al. 2021). However, there is the possibility of a decrease in efficiency due to ohmic losses (Ieropoulos et al. 2008). To avoid voltage reversal and high-power output, all the cells connected should be in proper working condition (Gurung & Oh 2012). In a study with stacked MFCs using synthetic wastewater it was found that series connection produces lower power compared to parallel arrangement due to a cross-conduction effect. Thus, to obtain high COD removal and current density, a parallel stack arrangement is preferred (Aelterman et al. 2006). Based on power output from 10 small units and its theoretical projection for 80 small units stacked together, Ieropoulos et al. (2008) suggested that the projected output could be 50 times higher than that of a single MFC of the same volume.

Domestic wastewater as well as wastewater such as swine wastewater, landfill leachate, urine waste, dairy manure, coke wastewater, and beverage wastewater are rich in nutrient content (Kumar & Pal 2015). Most of the reported studies on nutrient removal using MFCs are performed using synthetic domestic wastewater (Chen et al. 2015; Wang et al. 2019a, 2019c; Ye et al. 2019a, 2019b, 2020b), real domestic wastewater (Chen et al. 2017; Sun et al. 2018; Yang et al. 2018), swine wastewater (Ichihashi & Hirooka 2012; Doherty et al. 2015a, 2015b; Kim et al. 2015; Li et al. 2021a), dairy wastewater (Mansoorian 2016), slaughter house wastewater (Mohammed & Ismail 2018), leachate (Nguyen & Min 2020), and urine (Sharma & Mutnuri 2019; Sharma et al. 2021). Different mechanisms/pathways involved in nutrient removal and recovery by MFCs along with the efficiency of different systems are described in this section.

Nutrient removal and recovery by precipitation

In MFCs, precipitation of nutrients in a cathode chamber by pH control is a common method for removal of nutrients from wastewater. The precipitates generally show the elemental composition of struvite (MgNH4PO4.6H2O) or cattiite (Mg3(PO4)2.22H2O) in spectroscopy (Santoro et al. 2013; Ye et al. 2020a). Vivianite (Fe3(PO4)2·8H2O) precipitation also can be expected if there is the presence of iron (Liu et al. 2018). Struvite precipitation is considered as one of the methods to recover nutrients (Yetilmezsoy et al. 2017). Figure 3(a) shows the mechanisms in a dual-chamber MFC that remove nutrients as struvite.

Figure 3

Schematic representation of nutrient removal in (a) dual-chamber MFC by struvite precipitation, (b) microalgae-based MFC, (c) microbial nutrient recovery cell (MNRC), and (d) MFC integrated with constructed wetland.

Figure 3

Schematic representation of nutrient removal in (a) dual-chamber MFC by struvite precipitation, (b) microalgae-based MFC, (c) microbial nutrient recovery cell (MNRC), and (d) MFC integrated with constructed wetland.

Close modal
In dual-chambered MFCs, wastewater is treated in two stages. Initially, it is treated by electroactive microorganisms for removing organics and recovering energy in the anode chamber and later by conducting ion migration to recover phosphorus and nitrogen in the cathode chamber (Ye et al. 2019c). It has been observed that the concentration of ammonium in deionized water in the cathode chamber increases with time (Ye et al. 2019c). The ammonium ion passes through the IEM to the cathode chamber by diffusion and the electric field generated by MFC (Mohammed & Ismail 2018; Samrat et al. 2018). A cathode chamber can be provided with or without aeration. Aeration can significantly influence the nutrient removal efficiency in the cathode chamber, while the removal efficiency of the anode chamber is negligibly affected. In the cathode chamber, nitrogen and phosphorus are removed by the combined action of chemical precipitation and air stripping (Ye et al. 2019c). Struvite crystal precipitation occurs when the concentrations of Mg2+, NH4+, and PO43− exceed the solubility limit. The solubility decreases with an increase in pH value and the solubility is also affected by the ionic strength of the solution (Ichihashi & Hirooka 2012). The pH value near the cathode is found to be higher than other sites in the chamber due to hydroxyl ion formation. Even though the pH of the effluent is found to be less in some cases, researchers have suggested this possibility of local pH increase for the precipitation (Zhao et al. 2006). The pH in the cathode chamber is increased due to hydroxyl ions produced in the cathode according to the following chemical reactions:
formula
formula
Therefore, it has been suggested that the local pH increase near the cathode induced by the cathode reaction is the main reason for struvite precipitation. When the pH value is between 8.0 and 8.4, ammonium and phosphate can be precipitated with magnesium as per following reaction (Ye et al. 2019c):
formula

Since there is an increase in pH without adding external chemicals and generation of direct electricity, MFC can be a more economical and sustainable approach. Apart from precipitation, some amounts of nutrients are consumed by the bacterial consortium present in the anode chamber. In a single-chambered MFC with an air cathode, the crystals are obtained on the surface of the liquid side of the cathode.

A summary of different studies reported on the nutrient removal by precipitation using MFCs is presented in Table 1. It can be seen from this table that the removal efficiencies vary widely with respect to the membranes and electrode used, surface area of electrodes and membrane, and the characteristics of wastewater. The best removal/recovery of 94.9 and 97.58% for PO43− -P and NH4+-N, respectively was reported by Ye et al. (2019c) while treating synthetic municipal wastewater. A study conducted by Tao et al. (2015) reported that the maximum power density of a single chamber MFC was higher than that of the dual-chamber MFC. This study also concluded that single-chamber and dual-chamber MFCs can effectively remove phosphate, but their nitrogen removal efficiency varies considerably (Tao et al. 2015).

Table 1

Summary of reported studies on single-chamber and dual-chamber MFCs by precipitation

SI No.Type of wastewaterWastewater characteristicsType of MFCAnode chamberCathode chamberIon exchange membrane/SeparatorHRTCOD removalPhosphate removalAmmonia removalMaximum power density/voltage/current generationReference
Synthetic municipal wastewater COD-300 ± 15 mg/L NH4+-N-5.0 ± 0.15 mg/L
PO43−-P-1.0 ± 0.05 mg/L 
Double-chambered MFC (self-circulation mode) 350 mL, Cylindrical shaped graphite felt anode (3 cm diameter and 6 cm thickness) 350 mL, Carbon fiber brush coated with titanium bar cathode (approximately 3 cm length and 3 cm diameter) CEM (CMI7000) 24 h – >94.9% >97.58% 641.4 mV Ye et al. (2019c)  
FO membrane 24 h – 83.18% 98.81% – 
nonwoven 24 h – 90.6% 97.2% – 
Synthetic domestic wastewater COD- 600 mg/L Double chamber MFC (continuous) 350 mL, graphite felt anode (3 cm diameter and 6 cm thickness) 350 mL, Carbon fiber brush coated with titanium bar cathode (3 cm length and 3 cm diameter) CEM (CMI7000) 0.69 days 70% 71.5% removal in anode chamber, 24.4% average recovered in cathode chamber. 75.13% removal in anode chamber, 24.34% recovery in cathode chamber 253.84 mW/m3 Ye et al. (2019a)  
Synthetic domestic wastewater COD- 300 mg/L Double chamber MFC (continuous) 350 mL, Graphite felt anode (3 cm diameter and 6 cm thickness) 350 mL, Carbon fiber brush coated with titanium bar cathode (3 cm length and 3 cm diameter) CEM (CMI7000) 0.35–0.69 days >92% 12–14% removal in anode chamber, ∼83% recovered in cathode chamber 13–15% removal in anode chamber, ∼85% recovered in cathode chamber 253.84 mW/m3 Ye et al. (2020b)  
Industrial wastewater (Coors WWTP, Golden Colorado) COD-total- 1,243± 55 mg/L
COD-dissolved -989 ± 21 mg/L
Phosphate-18 ± 2 mg/L
Ammonia- 24 ± 3 mg/L 
Biochar-based microbial fuel cell Waste wood-derived biochar Waste wood-derived biochar CEM (CMI-7000) 95% TP -88% NH4-73% 6 W/m3 Huggins et al. (2016)  
Urine pH-6.3
COD-5,628 ± 52 mg/L
Ortho-P- 305 ± 14 mg/L
NH4-N-440 ± 32 mg/L 
Three-stage system (MFC- struvite precipitation- MFC system) 0.5 L, Stainless steel mesh (projected surface area of 255 cm20.5 L, Stainless steel mesh (projected surface area of 255 cm2CEM (CMI-7000) 48 h 75.55 ± 2.8% 90 ± 1.5% recovery 46 ± 2.16% recovery 14.5 mW/m2 Sharma et al. (2021)  
Synthetic wastewater NH4+-N-55.0 mg/L
PO43—P-122.9 mg/L 
Single-chamber MFC aeration 4 cm long 3 cm diameter, Carbon paper anode (projected area of 4 cm2Carbon cloth with platinum catalyst (0.5 mg Pt/cm2, liquid side) with four PTFE layers and one carbon base layer (air side) cathode – – 70% – – 560 mW/m2 Tao et al. (2015)  
Dual-chamber MFC 4 cm long, 3 cm diameter, carbon paper anode (projected area 7 cm24 cm long, 3 cm diameter, carbon cloth containing 0.5 mg Pt/cm2 cathode (projected area of 7 cm2Nafion 117 (7 cm2– 79% – – 528 mW/m2 
Swine wastewater COD- 60,000 mg/l phosphorus (SS)-670 mg/l Air-cathode single-chamber MFC 70 mL, Carbon felt anode (47 cm2 projected surface area) Carbon paper coated with platinum cathode (0.5 mg/cm2 of Pt/C) (effective surface area 47 cm2Polyester nonwoven cloth separator placed against both cathode and anode (7.7 cm diameter,0.5 mm thickness) 76–91% 79–82% 1.7 mW/m2 Ichihashi & Hirooka (2012)  
Synthetic wastewater Air cathode single-chamber MFC 70 mL, Carbon felt anode (projected area 47 cm2Wet porous carbon paper with coating of mg/cm2 of pt/C catalyst (projected area 47 cm2Nonwoven polyester separating cloth (2 × 3.5 0.5 cm thickness) – – 55% (as struvite) – – Hirooka & Ichihashi (2013)  
Synthetic domestic wastewater COD-300 ± 15 mg/L
NH4+- N- 5 mg/L
PO43—1 mg/L 
Dual compartment MFC Cylinder shaped graphite felt anode (3 cm diameter and 6 cm thickness) Carbon fiber brush cathode (3 cm length 3 cm diameter) CEM (CMI7000) 0.69 day 85.56% 11.37–13.33% removal and 76.03–83.23% recovery rate 85.11% recovery rate 230.17 mW/m2 Ye et al. (2019b)  
10 Urine pH- 6.3 ± 0.6
Conductivity-11.14 ± 0.12 mS/cm
COD-11,876.23 ± 22 mg/L
Ortho-P-201 ± 15 mg/L
NH4+-N-674 ± 23 mg/L
NO3- 246 ± 42 mg/L 
Dual-chambered MFC 230 mL, Stainless steel mesh (8 × 8 cm) Stainless steel mesh (8 × 8 cm) CEM (Ultrex CMI7000) 22 h 69.97 ± 2.2% Ortho-P-94.2 ± 2.3% 49.96 ± 0.9% 0.24 ± 0.15 W/m2 Sharma & Mutnuri (2019)  
SI No.Type of wastewaterWastewater characteristicsType of MFCAnode chamberCathode chamberIon exchange membrane/SeparatorHRTCOD removalPhosphate removalAmmonia removalMaximum power density/voltage/current generationReference
Synthetic municipal wastewater COD-300 ± 15 mg/L NH4+-N-5.0 ± 0.15 mg/L
PO43−-P-1.0 ± 0.05 mg/L 
Double-chambered MFC (self-circulation mode) 350 mL, Cylindrical shaped graphite felt anode (3 cm diameter and 6 cm thickness) 350 mL, Carbon fiber brush coated with titanium bar cathode (approximately 3 cm length and 3 cm diameter) CEM (CMI7000) 24 h – >94.9% >97.58% 641.4 mV Ye et al. (2019c)  
FO membrane 24 h – 83.18% 98.81% – 
nonwoven 24 h – 90.6% 97.2% – 
Synthetic domestic wastewater COD- 600 mg/L Double chamber MFC (continuous) 350 mL, graphite felt anode (3 cm diameter and 6 cm thickness) 350 mL, Carbon fiber brush coated with titanium bar cathode (3 cm length and 3 cm diameter) CEM (CMI7000) 0.69 days 70% 71.5% removal in anode chamber, 24.4% average recovered in cathode chamber. 75.13% removal in anode chamber, 24.34% recovery in cathode chamber 253.84 mW/m3 Ye et al. (2019a)  
Synthetic domestic wastewater COD- 300 mg/L Double chamber MFC (continuous) 350 mL, Graphite felt anode (3 cm diameter and 6 cm thickness) 350 mL, Carbon fiber brush coated with titanium bar cathode (3 cm length and 3 cm diameter) CEM (CMI7000) 0.35–0.69 days >92% 12–14% removal in anode chamber, ∼83% recovered in cathode chamber 13–15% removal in anode chamber, ∼85% recovered in cathode chamber 253.84 mW/m3 Ye et al. (2020b)  
Industrial wastewater (Coors WWTP, Golden Colorado) COD-total- 1,243± 55 mg/L
COD-dissolved -989 ± 21 mg/L
Phosphate-18 ± 2 mg/L
Ammonia- 24 ± 3 mg/L 
Biochar-based microbial fuel cell Waste wood-derived biochar Waste wood-derived biochar CEM (CMI-7000) 95% TP -88% NH4-73% 6 W/m3 Huggins et al. (2016)  
Urine pH-6.3
COD-5,628 ± 52 mg/L
Ortho-P- 305 ± 14 mg/L
NH4-N-440 ± 32 mg/L 
Three-stage system (MFC- struvite precipitation- MFC system) 0.5 L, Stainless steel mesh (projected surface area of 255 cm20.5 L, Stainless steel mesh (projected surface area of 255 cm2CEM (CMI-7000) 48 h 75.55 ± 2.8% 90 ± 1.5% recovery 46 ± 2.16% recovery 14.5 mW/m2 Sharma et al. (2021)  
Synthetic wastewater NH4+-N-55.0 mg/L
PO43—P-122.9 mg/L 
Single-chamber MFC aeration 4 cm long 3 cm diameter, Carbon paper anode (projected area of 4 cm2Carbon cloth with platinum catalyst (0.5 mg Pt/cm2, liquid side) with four PTFE layers and one carbon base layer (air side) cathode – – 70% – – 560 mW/m2 Tao et al. (2015)  
Dual-chamber MFC 4 cm long, 3 cm diameter, carbon paper anode (projected area 7 cm24 cm long, 3 cm diameter, carbon cloth containing 0.5 mg Pt/cm2 cathode (projected area of 7 cm2Nafion 117 (7 cm2– 79% – – 528 mW/m2 
Swine wastewater COD- 60,000 mg/l phosphorus (SS)-670 mg/l Air-cathode single-chamber MFC 70 mL, Carbon felt anode (47 cm2 projected surface area) Carbon paper coated with platinum cathode (0.5 mg/cm2 of Pt/C) (effective surface area 47 cm2Polyester nonwoven cloth separator placed against both cathode and anode (7.7 cm diameter,0.5 mm thickness) 76–91% 79–82% 1.7 mW/m2 Ichihashi & Hirooka (2012)  
Synthetic wastewater Air cathode single-chamber MFC 70 mL, Carbon felt anode (projected area 47 cm2Wet porous carbon paper with coating of mg/cm2 of pt/C catalyst (projected area 47 cm2Nonwoven polyester separating cloth (2 × 3.5 0.5 cm thickness) – – 55% (as struvite) – – Hirooka & Ichihashi (2013)  
Synthetic domestic wastewater COD-300 ± 15 mg/L
NH4+- N- 5 mg/L
PO43—1 mg/L 
Dual compartment MFC Cylinder shaped graphite felt anode (3 cm diameter and 6 cm thickness) Carbon fiber brush cathode (3 cm length 3 cm diameter) CEM (CMI7000) 0.69 day 85.56% 11.37–13.33% removal and 76.03–83.23% recovery rate 85.11% recovery rate 230.17 mW/m2 Ye et al. (2019b)  
10 Urine pH- 6.3 ± 0.6
Conductivity-11.14 ± 0.12 mS/cm
COD-11,876.23 ± 22 mg/L
Ortho-P-201 ± 15 mg/L
NH4+-N-674 ± 23 mg/L
NO3- 246 ± 42 mg/L 
Dual-chambered MFC 230 mL, Stainless steel mesh (8 × 8 cm) Stainless steel mesh (8 × 8 cm) CEM (Ultrex CMI7000) 22 h 69.97 ± 2.2% Ortho-P-94.2 ± 2.3% 49.96 ± 0.9% 0.24 ± 0.15 W/m2 Sharma & Mutnuri (2019)  

Nutrient removal and recovery by using photosynthetic microalgae

Microalgae-based wastewater treatment technology has been getting much attention currently as it is a green technology and is conceptualized on circular bioeconomy (Sharma et al. 2022). The algal biomass can assimilate nutrients and further can create economic benefits by producing value-added products like biodiesel and pigment (Yang et al. 2018; Arun et al. 2020). The removal efficiency also depends upon the type of microalgae used, and Chlamydomonas reinhardtii and Pseudokirchneriella subcapitata can be used to remove nutrients (Xiao et al. 2012). Adsorption, accumulation, biodegradation and immobilization are the important mechanisms adopted by microalgae for the remediation of pollutants in wastewater (Sharma et al. 2022).

A photosynthetic microalgal-based MFC is a promising technique that can be employed in nutrient removal. Microalgal application in MFC can reduce greenhouse gas emissions (Bolognesi et al. 2021). The schematic representation of a microalgae-based MFC is given in Figure 3(b). The predominant method of struvite precipitation in an MFC might negatively impact electricity generation and can be overcome by this alternative. Since microalgae can produce oxygen, the external aeration process can be eliminated, which increases the economic benefit. Photosynthesis, nitrification, aerobic denitrification, and autotrophic denitrification in the cathode chamber and their collaborative interactions play a significant role in nitrogen removal (Wang et al. 2019a). In general, microalgae-based MFCs remove phosphorus through both abiotic precipitation and biotic assimilation, while nitrogen is removed by assimilation and electron acceptor in the cathode (Yang et al. 2018). Li et al. (2020) based on studies on microalgae-based MFC found that microalgae present in the cathode chamber alone can remove up to 55.8% of total nitrogen (TN) and 48.7% of total phosphate (TP). The presence of microalgae can also increase power generation in MFCs (Yang et al. 2018).

A summary of various studies conducted to remove nutrients from wastewater using microalgae-based MFCs is given in Table 2. The ammonia or nitrogen recovery of microalgae-based MFCs is higher than those systems that recover nutrients by precipitation. A complete removal of ammonia from synthetic wastewater was also reported (Don & Babel 2021). A study on nutrient removal in swine wastewater using airlift type photosynthetic MFCs by Li et al. (2021) has been reported to achieve COD, NH4+-N, and TP removal efficiencies of 96.3, 99.1 and 98.9%, respectively, using Chlorella vulgaris.

Table 2

Summary of reported studies on microalgae-based MFCs for nutrient removal

SI No.Type of wastewaterWastewater characteristicsType of MFCMicroalgaeAnode chamberCathode chamberIon exchange membrane/SeparatorHRTCOD removalPhosphate removalAmmonia removalMaximum power density/voltage/currentReference
Synthetic domestic wastewater – Immobilized microalgal-based photosynthetic MFC (PMFC) Chlorella vulgaris 400 mL, Carbon brush (7.5 × 4 cm) 400 mL, Carbon brush (7.5 × 4 cm) PEM (Nafion 117–8.5 cm212 h sCOD -93.2% 82.7% NH4+-N-95.9%
TN-95.1% 
466.9 mW/m3 Wang et al. (2019a)  
Synthetic wastewater NH4+-N-90 mg/L Dual-chambered MFC assisted with algae in cathode chamber Chlorella sp. (single celled), Desmodesmus sp and Scenedesmus sp. 205 mL, Carbon fiber brush (3 × 2.5 cm) 20 mL, Carbon fiber brush (3 × 2.5 cm) PEM (Nafion 117) – – – 99.6% 0.35 A Kakarla & Min (2019)  
Swine wastewater COD -7,786 mg/L
TOC-2,094 mg/L
TN-2,048 mg/L TP-124.7 mg/L
NH4+-N-1,820 mg/L
pH -7.68 
Airlift-type photosynthetic microbial fuel cell (APMFC) Chlorella vulgaris 400 mL, Carbon brush (length of 9.0 cm, diameter of 3.5 cm) 400 mL, Carbon fiber cloth (6 cm × 8 cm ¼ 48 cm2) containing Pt catalyst PEM (Nafion 117) – 96.3% TP-98.9% NH4+-N-99.1%
TN-98.3% 
3.66 W/m3 Li et al. (2021a)  
,4 Domestic wastewater COD-186.8 to 327.9 mg/L
TN-25.3 to 52.5 mg/L
TP- 2.9 to 8.3 mg/L 
Algae biofilm microbial fuel cell (ABMFC) Scenedesmus quadricauda Carbon cloth cathode (diameter 90 mm, thickness 8 mm) interwoven with titanium wire in the lower chamber of the MFC. Carbon cloth cathode (diameter 90 mm, thickness 8 mm) woven with titanium placed on the water surface Glass wool (thickness 20 mm, diameter 110 mm) 12days 81.9% 96.4 % 95.5% 162.93 mW/m2 Yang et al. (2018)  
,5 Leachate and wastewater mix NH4+-N- 403.4 ± 27.9 mg/L Algae cathode microbial fuel cell Mixed algal bioreactor 260 mL, Carbon fiber brush (L × D = 3 × 2.5 cm2230 mL, Carbon fiber brush (L × D = 3 × 2.5 cm2CEM (CMI-7000) 60 h – Soluble phosphate -86.3% TN-58.85%
NH4+–N-76% 
1.4 ± 0.4 mV (current generation almost zero) Nguyen & Min (2020)  
,6 Synthetic wastewater COD-1,500 mg/L
NH4+-N- 50 mg/L 
Photosynthetic MFC Chlorella vulgaris and Scenedesmus quadricauda Carbon fiber cloths (surface area of 204 cm2Carbon fiber cloths (surface area of 204 cm2CEM (CMI-7000) – – – 100% 16.72 mW/m2 Don & Babel (2021)  
,7 anaerobically digested effluent from kitchen waste COD- 6,015 ± 280 mg/L
NH4+-N- 2,365 ± 160 mg/L
TP- 95 ± 3 mg/L 
Photosynthetic microbial fuel cell stack Golenkinia sp. 0.36 L, Carbon brush 16 L, Carbon cloth CEM – – – 98% 2.34 W/m3 Yang et al. (2019)  
SI No.Type of wastewaterWastewater characteristicsType of MFCMicroalgaeAnode chamberCathode chamberIon exchange membrane/SeparatorHRTCOD removalPhosphate removalAmmonia removalMaximum power density/voltage/currentReference
Synthetic domestic wastewater – Immobilized microalgal-based photosynthetic MFC (PMFC) Chlorella vulgaris 400 mL, Carbon brush (7.5 × 4 cm) 400 mL, Carbon brush (7.5 × 4 cm) PEM (Nafion 117–8.5 cm212 h sCOD -93.2% 82.7% NH4+-N-95.9%
TN-95.1% 
466.9 mW/m3 Wang et al. (2019a)  
Synthetic wastewater NH4+-N-90 mg/L Dual-chambered MFC assisted with algae in cathode chamber Chlorella sp. (single celled), Desmodesmus sp and Scenedesmus sp. 205 mL, Carbon fiber brush (3 × 2.5 cm) 20 mL, Carbon fiber brush (3 × 2.5 cm) PEM (Nafion 117) – – – 99.6% 0.35 A Kakarla & Min (2019)  
Swine wastewater COD -7,786 mg/L
TOC-2,094 mg/L
TN-2,048 mg/L TP-124.7 mg/L
NH4+-N-1,820 mg/L
pH -7.68 
Airlift-type photosynthetic microbial fuel cell (APMFC) Chlorella vulgaris 400 mL, Carbon brush (length of 9.0 cm, diameter of 3.5 cm) 400 mL, Carbon fiber cloth (6 cm × 8 cm ¼ 48 cm2) containing Pt catalyst PEM (Nafion 117) – 96.3% TP-98.9% NH4+-N-99.1%
TN-98.3% 
3.66 W/m3 Li et al. (2021a)  
,4 Domestic wastewater COD-186.8 to 327.9 mg/L
TN-25.3 to 52.5 mg/L
TP- 2.9 to 8.3 mg/L 
Algae biofilm microbial fuel cell (ABMFC) Scenedesmus quadricauda Carbon cloth cathode (diameter 90 mm, thickness 8 mm) interwoven with titanium wire in the lower chamber of the MFC. Carbon cloth cathode (diameter 90 mm, thickness 8 mm) woven with titanium placed on the water surface Glass wool (thickness 20 mm, diameter 110 mm) 12days 81.9% 96.4 % 95.5% 162.93 mW/m2 Yang et al. (2018)  
,5 Leachate and wastewater mix NH4+-N- 403.4 ± 27.9 mg/L Algae cathode microbial fuel cell Mixed algal bioreactor 260 mL, Carbon fiber brush (L × D = 3 × 2.5 cm2230 mL, Carbon fiber brush (L × D = 3 × 2.5 cm2CEM (CMI-7000) 60 h – Soluble phosphate -86.3% TN-58.85%
NH4+–N-76% 
1.4 ± 0.4 mV (current generation almost zero) Nguyen & Min (2020)  
,6 Synthetic wastewater COD-1,500 mg/L
NH4+-N- 50 mg/L 
Photosynthetic MFC Chlorella vulgaris and Scenedesmus quadricauda Carbon fiber cloths (surface area of 204 cm2Carbon fiber cloths (surface area of 204 cm2CEM (CMI-7000) – – – 100% 16.72 mW/m2 Don & Babel (2021)  
,7 anaerobically digested effluent from kitchen waste COD- 6,015 ± 280 mg/L
NH4+-N- 2,365 ± 160 mg/L
TP- 95 ± 3 mg/L 
Photosynthetic microbial fuel cell stack Golenkinia sp. 0.36 L, Carbon brush 16 L, Carbon cloth CEM – – – 98% 2.34 W/m3 Yang et al. (2019)  

Other mechanisms of nutrient removal by MFCs

Other than precipitation and absorption by microalgae, nutrients are removed by various other mechanisms in MFCs. The high pH at the cathode causes the production of volatile ammonia, which can be removed by air stripping and it can be recovered by adsorbing it in acid solution to produce ammonium salts (Kuntke et al. 2012; Ye et al. 2020a). Autotrophic nitrification and denitrification, and ammonia stripping are the two main mechanisms of removal of ammonia other than precipitation in a single-chamber MFC. Littfinski et al. (2022) reported that ammonia volatilization alone contributes 22 to 63% of total ammonia nitrogen (TAN) removal in a single-chamber MFC. In biocathode MFCs, autotrophic denitrifying bacteria can reduce nitrate to nitrogen gas (Al-Mamun et al. 2017). However, the recovery of ammonia is mostly reduced due to nitrification and denitrification processes (Ye et al. 2019a). It has been reported that electrogenesis also promotes denitrification, and species like Dechloromonas and Geobacter have the capacity for denitrification (Li et al. 2021b).

Wastewater discharged from industries such as tanneries and mining and swine wastewater contains both ammonium and sulphide. In such wastewaters, the S/N molar ratio is an important parameter with a desirable value of 3 for coupled system of nitrifying sulphide removal MFC (N-MFC) and denitrifying sulphide removal MFC (D-MFC). N-MFC consists of an oxic-cathode and D-MFC consists of an anoxic-cathode, and sulphide can act as electron donor in both cases. This coupled system was able to achieve 58.7 ± 1.3% TN removal efficiency (Chen et al. 2019). The dual MFC system developed to remove the dye Victoria blue R (VBR) achieved complete ammonia removal (Jayashree et al. 2019). In this system, two MFCs were coupled together. For anaerobic decomposition of VBR in the first MFC, the anode chamber was inoculated with S. putrefaciens, and A. calcoaceticus was cultured in the biocathode of a second MFC for aerobic decomposition (Wu et al. 2020). The use of a seawater bacterial consortium for denitrification in MFCs was also explored by researchers and found it to be a feasible approach that needs further studies (Samrat et al. 2018; Pepè Sciarria et al. 2019). The incorporation of a bioactive oxygen consuming unit (OCU) as separator in a single-chamber MFC has a higher oxidation peak value which increases with increase in thickness of OCU. This is because OCU creates an oxygen gradient between the anode and cathode, thus reducing oxygen diffusion to the anode and enhancing the electrochemical reaction (Elmaadawy et al. 2020). The microbial desalination cell (MDC) is a technology in which some aspects of MFCs and electrodialysis are amalgamated (Gujjala et al. 2022). This consists of three chambers (anode, cathode and desalination chambers) which are separated by a CEM on one side and an AEM on the other side. A modified version with four chambers with an acid production chamber that is separated from the anode chamber by a bipolar membrane has also been explored by various researchers (Rahman et al. 2021).

The microbial nutrient recovery cell or MNRC represented in Figure 3(c) is a type of modified MFC for nutrient recovery (Shahid et al. 2021a). More than 95% nutrient removal efficiency was possible by using nutrient recovery cell (Chen et al. 2017). These three chambered nutrient recovery cell reactor systems containing a middle recovery chamber separated by a CEM on the anode side and an AEM on the cathode side show a high nutrient removal efficiency. In this system, nutrients from the wastewater are collected by the influence of bioelectricity produced from the decomposition of organic matter. The wastewater circulates between the anode and cathode chambers and the recovery solution, which receives nutrients circulates individually. Ammonium ions and phosphate ions are pushed from the anode and cathode sides, respectively, into the recovery chamber. Concentrated nutrient ions in the recovery solution are recovered in the form of struvite. The concentration of recovery solution also has a significant influence on the overall performance of the MNRC (Chen et al. 2015).

Studies on various modified MFC systems for removal of nutrients are summarized in Table 3. The MNRC system was reported to achieve removal efficiencies of 99.5, 98.27, and 99–100% of COD, ammonium and phosphate respectively using a heat-treated carbon brush as the anode and a carbon cloth coated with platinum as the cathode, achieving a power density of 1,000 mW/m2 (Shahid et al. 2021b). In this study it was concluded that the carbon brush anode was able to achieve higher power production compared to a stainless steel anode with other experimental conditions remaining the same.

Table 3

Summary of reported studies on modified MFC systems

SI No.Type of wastewaterWastewater characteristicsType of MFCAnode chamberCathode chamberIon exchange membrane/SeparatorHRTCOD removal (%)Phosphate removal (%)Ammonia removal (%)Maximum power density/voltage/ currentReference
Synthetic waste water NH4+-28.9 ± 0.7 mg N/L (oxic cathode chamber) Sulphide-(64, 128, 192 and 256 mg S/L) Two dual-chambered MFC coupled (nitrifying sulphide removal N-MFC and denitrifying sulphide removal D-MFC) 200 cm3, Carbon brush prepared with carbon fiber filaments twining on a titanium wire anode 200 cm3, Carbon brush prepared with carbon fiber filaments twinning on a titanium wire cathode PEM (Nafion 117) – – – TN-58.7 ± 1.3% 13.59 ± 0.31 W/m3 Chen et al. (2019)  
Landfill leachate  COD-2,005.5 mg/L
Ammonia nitrogen -251.4 mg/L 
Cathodic algal biofilm (Chlorella vulgaris) MFC equipped with a bioactive oxygen consuming unit (AB-OCU-MFC) Circular piece of carbon felt anode (diameter of 25 mm and thickness 10 mm.) Air cathode electrode (diameter of 48 mm) prepared from stainless steel mesh loaded with catalyst Circular carbon felts (28 mm diameter and 10- or 20-mm thickness) OCUs – 86.0 ± 1.25% – 89.4 ± 0.85% 0.39 V Elmaadawy et al. (2020)  
Synthetic wastewater COD-322 mg/L
PO43—P-20 mg/L
NH4+-N-20 mg/L
NO3-N-20 mg/L 
Three chamber microbial nutrient recovery cell (MNRC) Carbon brush with heat treatment (projected area of 19.6 cm 2Carbon cloth (Pt coating at water side and PTFE coating at air facing side) CEM (CMI7000S), AEM (AMI7001S) – 99.5% (*t = 120 h) 99–100% (*t = 168 h) NH4+-N-98.27%(*t = 144 h)
NO3N- 90.06% (*t = 168 h) 
1,000 mW/ m2 Shahid et al. (2021b)  
Carbon brush with APTES modification 99%(*t = 120 h) 99–100% (*t = 168 h) NH4+-N-97.98%(*t = 144 h)
NO3N-91% (*t = 168 h) 
850 mW/m2 
Stainless steel brush with heat treatment 80% (*t = 120 h) 78.77% (*t = 168 h) NH4+-N
97.16%(*t = 144 h)
NO3N 73.28% (*t = 168 h) 
370 mW/m2 
Municipal wastewater – Microbial nutrient recovery system (MNRS) Carbon brush and Air-cathodes 30% wet proofed carbon cloth with an inside catalyst layer of 0.5 mg/cm2 Pt on carbon black with 5 wt % CEM(CMI7000S)
AEM(AMI-7001S) 
– 82.3 ± 4.1% 83% (recover) 80% (recover) 800 mW/m2 Shahid et al. (2021a)  
Stainless-steel brush 63 ± 3.1% 70%(recover) 70% (recovery) ∼400 mW/m2 
Synthetic domestic wastewater COD-369 ± 21 mg/L
NH4+-N-23.8 ± 1.3 mg/L
PO43—P-6.4 ± 0.6 mg/L 
Microbial nutrient recovery cell (MNRC) (3.6 mL recovery chamber) 21.2 mL, Granular activated carbon. 3.6 mL, The air cathode made of carbon cloth (30% wet-proofing) with 0.5 mg/cm2 platinum catalyst and four polytetrafluoroethylene (PTFE) diffusion layers. CEM (Ultrex CMI7000), AEM (Ultrex AMI-7001) – >82% >64% >96% 0.56 A/m2 Chen et al. (2015)  
Domestic wastewater COD = 463 mg/L,
PO43−-P = 7.6 mg/L,
NH4+-N = 47.4 mg/L 
Enlarged microbial nutrient recovery cell (EMNRC) Granular activated carbon (∼1 mm in diameter, ∼2–5 mm in length) anode 30% wet-proofing carbon cloth with a platinum loading of 0.5 mg/cm2 and four diffusion layers of polytetrafluoroethylene cathode CEM, (Ultrex CMI7000)
AEM, (Ultrex AMI-7001) 
– > 70% > 55% (89% Recovered as struvite) > 80% (62% Recovered as struvite) 2.3–3.1 mA Sun et al. (2018)  
Sludge reject water samples and livestock wastewater Sludge reject water: livestock wastewater = 70%:30% (v: v) Microbial nutrient recovery cell (MNRC) 220 mL, Carbon-fiber anode 220 mL, Air cathode made of carbon cloth CEM-(CMI-7000)
AEM- (AMI-7001) 
– – – 79.8 ± 7.7% 14.10 ± 1.14 A/m3 El-Qelish & Mahmoud (2022)  
Domestic wastewater COD-331 ± 25 mg/L, TN-84.4 ± 7.9 mg/L, NH4+-N-58.2 ± 6.7 mg/L, TP-9.4 ± 0.2 mg/L Advanced microbial nutrient recovery cell (AMNRC) 4 L 4 L CEM
AEM 
10 h 95.8 ± 0.5% TP- 96.9 ± 0.3% 96.9 ± 0.2% ∼40 mA Chen et al. (2017)  
Primary effluent from wastewater treatment plant TCOD- 155 ± 37 mg/L
SCOD-73 ± 23 mg/L
NH4+-25.7 ± 5.5 mg N/L
TSS- 72.9 ± 16.6 mg/L 
96 tubular MFC modules, which were placed as 12 × 8 arrays with 12 MFCs in each row and 8 rows in total Carbon brush Carbon cloth coated with nitrogen doped activated carbon powder CEM, (Ultrex CMI7000) 18 h >75% – 68% ∼200 mW Ge & He (2016)  
10 Dairy industrial wastewater COD-3,620 mg/L
BOD5–2,115 mg/L
Total P-187 mg/L
NH3-167 mg/L
NH4+- 174 mg/L
TSS -1,430 mg/L
VSS- 647 mg/L
SO42−-835 mg/L
EC-2,176 ms/cm
pH -8.5–10.3 
Catalyst less mediator less dual-chamber MFC, continuous mode 2 L, Graphite plate (14 × 6 × 0.5 cm32 L, Graphite plate (14 × 6 × 0.5 cm3PEM (Nafion 117) 5days 90.46% Dissolved phosphate-31.18%
Phosphate in suspends solid-72.45% 
NH3-73.22%
NH4+ -69.43% 
621.17 mW/m2 Mansoorian (2016)  
11 Synthetic wastewater (simulate eutrophic wastewater) COD- 20 ± 3 mg/L
NH4+-N- 3.2 ± 0.1 mg/L
NO3-N- 3.1 ± 0.1 mg/L
PO43—P- 0.63 ± 0.02 mg/L 
Photomicrobial nutrients recovery cell (PNRC)
(Chlorella vulgaris) 
Carbon brush (3 cm diameter, 3 cm length) Carbon cloth (with 5 cm2 projected surface area) coated with Pt 0.5 mg /cm2CEM, AEM – 94.5% 94.4% 91.8% 472.3 mW/m2 Jiang et al. (2019)  
SI No.Type of wastewaterWastewater characteristicsType of MFCAnode chamberCathode chamberIon exchange membrane/SeparatorHRTCOD removal (%)Phosphate removal (%)Ammonia removal (%)Maximum power density/voltage/ currentReference
Synthetic waste water NH4+-28.9 ± 0.7 mg N/L (oxic cathode chamber) Sulphide-(64, 128, 192 and 256 mg S/L) Two dual-chambered MFC coupled (nitrifying sulphide removal N-MFC and denitrifying sulphide removal D-MFC) 200 cm3, Carbon brush prepared with carbon fiber filaments twining on a titanium wire anode 200 cm3, Carbon brush prepared with carbon fiber filaments twinning on a titanium wire cathode PEM (Nafion 117) – – – TN-58.7 ± 1.3% 13.59 ± 0.31 W/m3 Chen et al. (2019)  
Landfill leachate  COD-2,005.5 mg/L
Ammonia nitrogen -251.4 mg/L 
Cathodic algal biofilm (Chlorella vulgaris) MFC equipped with a bioactive oxygen consuming unit (AB-OCU-MFC) Circular piece of carbon felt anode (diameter of 25 mm and thickness 10 mm.) Air cathode electrode (diameter of 48 mm) prepared from stainless steel mesh loaded with catalyst Circular carbon felts (28 mm diameter and 10- or 20-mm thickness) OCUs – 86.0 ± 1.25% – 89.4 ± 0.85% 0.39 V Elmaadawy et al. (2020)  
Synthetic wastewater COD-322 mg/L
PO43—P-20 mg/L
NH4+-N-20 mg/L
NO3-N-20 mg/L 
Three chamber microbial nutrient recovery cell (MNRC) Carbon brush with heat treatment (projected area of 19.6 cm 2Carbon cloth (Pt coating at water side and PTFE coating at air facing side) CEM (CMI7000S), AEM (AMI7001S) – 99.5% (*t = 120 h) 99–100% (*t = 168 h) NH4+-N-98.27%(*t = 144 h)
NO3N- 90.06% (*t = 168 h) 
1,000 mW/ m2 Shahid et al. (2021b)  
Carbon brush with APTES modification 99%(*t = 120 h) 99–100% (*t = 168 h) NH4+-N-97.98%(*t = 144 h)
NO3N-91% (*t = 168 h) 
850 mW/m2 
Stainless steel brush with heat treatment 80% (*t = 120 h) 78.77% (*t = 168 h) NH4+-N
97.16%(*t = 144 h)
NO3N 73.28% (*t = 168 h) 
370 mW/m2 
Municipal wastewater – Microbial nutrient recovery system (MNRS) Carbon brush and Air-cathodes 30% wet proofed carbon cloth with an inside catalyst layer of 0.5 mg/cm2 Pt on carbon black with 5 wt % CEM(CMI7000S)
AEM(AMI-7001S) 
– 82.3 ± 4.1% 83% (recover) 80% (recover) 800 mW/m2 Shahid et al. (2021a)  
Stainless-steel brush 63 ± 3.1% 70%(recover) 70% (recovery) ∼400 mW/m2 
Synthetic domestic wastewater COD-369 ± 21 mg/L
NH4+-N-23.8 ± 1.3 mg/L
PO43—P-6.4 ± 0.6 mg/L 
Microbial nutrient recovery cell (MNRC) (3.6 mL recovery chamber) 21.2 mL, Granular activated carbon. 3.6 mL, The air cathode made of carbon cloth (30% wet-proofing) with 0.5 mg/cm2 platinum catalyst and four polytetrafluoroethylene (PTFE) diffusion layers. CEM (Ultrex CMI7000), AEM (Ultrex AMI-7001) – >82% >64% >96% 0.56 A/m2 Chen et al. (2015)  
Domestic wastewater COD = 463 mg/L,
PO43−-P = 7.6 mg/L,
NH4+-N = 47.4 mg/L 
Enlarged microbial nutrient recovery cell (EMNRC) Granular activated carbon (∼1 mm in diameter, ∼2–5 mm in length) anode 30% wet-proofing carbon cloth with a platinum loading of 0.5 mg/cm2 and four diffusion layers of polytetrafluoroethylene cathode CEM, (Ultrex CMI7000)
AEM, (Ultrex AMI-7001) 
– > 70% > 55% (89% Recovered as struvite) > 80% (62% Recovered as struvite) 2.3–3.1 mA Sun et al. (2018)  
Sludge reject water samples and livestock wastewater Sludge reject water: livestock wastewater = 70%:30% (v: v) Microbial nutrient recovery cell (MNRC) 220 mL, Carbon-fiber anode 220 mL, Air cathode made of carbon cloth CEM-(CMI-7000)
AEM- (AMI-7001) 
– – – 79.8 ± 7.7% 14.10 ± 1.14 A/m3 El-Qelish & Mahmoud (2022)  
Domestic wastewater COD-331 ± 25 mg/L, TN-84.4 ± 7.9 mg/L, NH4+-N-58.2 ± 6.7 mg/L, TP-9.4 ± 0.2 mg/L Advanced microbial nutrient recovery cell (AMNRC) 4 L 4 L CEM
AEM 
10 h 95.8 ± 0.5% TP- 96.9 ± 0.3% 96.9 ± 0.2% ∼40 mA Chen et al. (2017)  
Primary effluent from wastewater treatment plant TCOD- 155 ± 37 mg/L
SCOD-73 ± 23 mg/L
NH4+-25.7 ± 5.5 mg N/L
TSS- 72.9 ± 16.6 mg/L 
96 tubular MFC modules, which were placed as 12 × 8 arrays with 12 MFCs in each row and 8 rows in total Carbon brush Carbon cloth coated with nitrogen doped activated carbon powder CEM, (Ultrex CMI7000) 18 h >75% – 68% ∼200 mW Ge & He (2016)  
10 Dairy industrial wastewater COD-3,620 mg/L
BOD5–2,115 mg/L
Total P-187 mg/L
NH3-167 mg/L
NH4+- 174 mg/L
TSS -1,430 mg/L
VSS- 647 mg/L
SO42−-835 mg/L
EC-2,176 ms/cm
pH -8.5–10.3 
Catalyst less mediator less dual-chamber MFC, continuous mode 2 L, Graphite plate (14 × 6 × 0.5 cm32 L, Graphite plate (14 × 6 × 0.5 cm3PEM (Nafion 117) 5days 90.46% Dissolved phosphate-31.18%
Phosphate in suspends solid-72.45% 
NH3-73.22%
NH4+ -69.43% 
621.17 mW/m2 Mansoorian (2016)  
11 Synthetic wastewater (simulate eutrophic wastewater) COD- 20 ± 3 mg/L
NH4+-N- 3.2 ± 0.1 mg/L
NO3-N- 3.1 ± 0.1 mg/L
PO43—P- 0.63 ± 0.02 mg/L 
Photomicrobial nutrients recovery cell (PNRC)
(Chlorella vulgaris) 
Carbon brush (3 cm diameter, 3 cm length) Carbon cloth (with 5 cm2 projected surface area) coated with Pt 0.5 mg /cm2CEM, AEM – 94.5% 94.4% 91.8% 472.3 mW/m2 Jiang et al. (2019)  

*Time of operation.

Integrated systems for nutrient removal

MFCs can be integrated with various other treatment technologies to overcome the limitations of the existing technologies or to improve the nutrient recovery/removal. Results of various MFC-integrated systems reported for removal of nutrients from different types wastewater are summarized in Table 4. MFCs integrated with constructed wetlands, aerobic and anoxic bioreactors, biofilters, membrane bioreactor and anaerobic digestors were used in different studies. The most explored integrated system is constructed wetland–MFC due to minimal construction and operational costs.

Table 4

Summary of reported studies on different MFC-integrated systems for nutrient removal

SI No.Type of wastewaterWastewater characteristicsType of MFCAnode chamberCathode chamberIon exchange membrane/SeparatorHRTCOD removalPhosphate removalAmmonia removalMaximum power density/voltage/currentReference
1. Swine slurry COD- 411–854 mg/L
TN-63 ± 7.5 mg/L
NH4+-N-40 ± 5.3 mg/L
TP -8.9 ± 2.1 mg/L
Reactive phosphorus (RP)- 6.2 ± 1.5 mg/L 
Alum sludge-based constructed wetland incorporating microbial fuel cell technology 1.1 ± 0.09 L, packing granular graphite anode (diameter 8–13 mm, initial porosity of 0.38) 1.1 ± 0.09 L, packing granular graphite cathode (diameter 8–13 mm, initial porosity of 0.38) Glass wool 1day 80% 85% 75% 0.268 W/m3 Doherty et al. (2015b)  
Swine wastewater COD-583 ± 92 mg/L
TN- 63 ±7.5 mg/L
NH4+-N-40 ± 5.3 mg/L
TP -8.9 ± 2.1 mg/L
PO4-P-6.2 ± 1.5 mg/L 
Constructed wetland -MFC Graphite granule with graphite rod anode Graphite granule with graphite rod cathode Glass wool 1 day 64 ± 4.6% PO4-P-90 ±2.2%
TP- 85 ± 4.0% 
NH4+-N-75 ± 3.1%
TN- 58 ± 3.1% 
0.276 W/m3 Doherty et al. (2015a)  
Municipal wastewater NH4+-N-21.3 ± 7.5 mg/L
TP-10.1 ± 3.6 mg/L 
MFC-based horizontal flow constructed wetland (Phragmites australis and Chrysopogon zizanioidesAluminium plate anode Aluminium plate cathode – – 80–100% ≥93% 55 t-92% 38.6 mW/m2 Saeed et al. (2022)  
Synthetic wastewater COD-200 mg/L, NO3N-40–80 mg/L, TP -4–8 mg/L Pyrite-based constructed wetland-microbial fuel cell (PCW-MFC) (Canna indica plant) Carbon fiber felts anode (12 cm in diameter, 1 mm in thickness) Carbon fiber felts cathode (12 cm in diameter, 1 mm in thickness) – 6 h 71.9 ± 3.6% TP-89.2 ± 2.7% NO3-N -67.5 ± 4.4% 2.67 mW/m2 Ge et al. (2020)  
Synthetic domestic wastewater NH3-N-25 mg/L NO2–N-0.1 mg/L,
NO3–N-0.5 mg/L,
organicN-15 mg/L
TN-40.6 mg/L
PO43−-P-4 mg/L
P3O105—P-1 mg/L,
TP-5 mg/L.
COD- 50–360 mg/L 
Constructed wetland-MFC (Canna indicaCarbon fiber brush anode Graphite plate cathode – 1.5 day – – TN- 90.30–91.46% 3.25 mW/m3 Wang et al. (2019c)  
Synthetic wastewater COD-314.8 ± 13 mg/L Up-flow constructed wetland-MFC (UFCW-MFC) (Typha latifoliaCarbon felt anode (total surface area 280 cm2Carbon felt cathode (total surface area 280 cm2– 1 day 100% – 91% 6.12 mW/m2 Oon et al. (2015)  
Secondary effluent from WWTP -synthetic WW COD-58.0 ± 2.2 mg/L,
TN-14.7 ± 1.5 mg/L,
NH4+-N-5.6 ± 1.1 mg/L
NO3-N-10.8 ± 1.4 mg/L 
Constructed wetland -MFC (corncobs were added to enhance the performance) Graphite plate anode (200 × 100 × 8 mm) Graphite plate cathode (200 × 100 × 8 mm) – 48 h 89.9% – NH4+-N-99.7%
NO3N- 100% 
1.92 mW/m2 Tao et al. (2022)  
Synthetic wastewater COD-150 mg/L,
NH4+-N-30 mg/L 
Tidal flow constructed wetland – MFC (TFCW-MFC) (Canna indica) Layer of Activated carbon granules and graphite felt (20 cm length × 10 cm width × 0.6 cm thickness) Carbon felt (14 cm outer diameter × 7 cm inner diameter × 0.6 cm thickness) – 7 Days >85% – TN- 52.89 ± 3.16% – Xu et al. (2021)  
Swine wastewater TCOD-73,828 ± 1,804 mg/L
SCOD-43,489 ± 1,146 mg/L
T-N-5,152 ± 266 mg/L
TAN-4,199 ± 27 mg/L
T-P -818 ± 19 mg/L 
Anaerobic digestor-MFC (3 identical air cathode MFCs) 320 mL, carbon felt anode Carbon cloth coated with a Pt catalyst (0.5 mg/cm2) cathode Nafion NAF NR212 – – – TAN- 77.5% 33 mW/m2 Kim et al. (2015)  
10 slaughterhouses wastewater COD-980–1,000 mg/L
NH4+-150–250 mg/L
NO3-15–20 mg/L
NO2-6–12 mg/L
Electrical conductivity (EC)- 920–1,280 μS/cm
pH – 6.3–7.1 
Microbial fuel cell, aerobic bioreactor, and anoxic bioreactor (MFC-AB-ANB) Uncoated plane graphite rod (effective surface area of 185.35 cm2Graphite granules (specific surface of 0.0832 m2 /g, and granular size diameter range of 2–4 mm) CEM (CMI- 7000 s) – 99% – 99.3% 162.55 mW/m2 Mohammed & Ismail (2018)  
11 Municipal wastewater COD-266.7 mg/L
NH4+-N-52.3 mg/L
PO43—P-6.2 mg/L 
Integrated photo bio-electrochemical system (Microbial fuel cell inside an algal bioreactor- Pseudokirchneriella subcapitata∼300 mL, 20 cm long carbon brush anode Layer of carbon cloth with Pt/C as catalysts cathode CEM, Ultrex CMI7000 12.5 h 92.4% 82.3% 98.6% 2.2 ± 0.2 W/m3 Xiao et al. (2012)  
12 Synthetic wastewater NaAc- 600 mg/L
NO3 − 95.0 mg/L 
MFC coupled with up-flow denitrification biofilter (BF) Graphite particle filter as bioanode Air cathode made of stainless steel – 24 h 87.50–90.86% – denitrification efficiency - 89.31–98.60% 0.48 mA Li et al. (2021b)  
13 Synthetic wastewater COD-1,505.61 ± 681.54 mg/L
NH4+-21.72 ± 7.99 mg/L
Phosphate-17.13 ± 5.77 mg/L 
Algal (Chlorella vulgaris) assisted constructed wetland (Canna indica)-MFC integrated with sand filter 600 mL, Graphite granules anode 750 mL, Carbon felt cathode Earthen membrane 5 days 96.37 ± 2.6% 69.03 ± 10.14% 85.14 ± 10.73% 33.14 mWm−3 Gupta et al. (2021)  
14 Domestic wastewater NH3-N-32 ± 4.28 mg/L
SCOD-1,080 ± 160 mg/L 
MFC-MBR Graphite brush anode (2.5 cm diameter × 2.5 cm length) Conductive UF membranes biocathodes prepared by dispersing multiwalled carbon nanotubes (MCNTs) (specific surface area of 117 m2/g) – 2–3 days SCOD-97.3 ± 1.1% – 97.3 ± 1.6% 0.38 W/m2 Malaeb et al. (2013)  
Platinum-based MCNT/polyester UF membrane cathode – 2–3 days 96.9 ± 0.6% – 95.2 ± 2.9% 0.82 W/m2 
15 Domestic wastewater CODtotal 323 mg/L
Ammonia 41 mg/L
Sulphate 102 mg/L
Orthophosphate9 mg/L 
Horizontal subsurface constructed wetland 20 cylindrical graphite rods wrapped in stainless steel (1 cm length and 0.5 cm diameter each) 20 cylindrical graphite rods wrapped in stainless steel (1 cm length and 0.5 cm diameter each) – 2.6 days 61% – 58% 36 mW/m2 Corbella et al. (2015)  
SI No.Type of wastewaterWastewater characteristicsType of MFCAnode chamberCathode chamberIon exchange membrane/SeparatorHRTCOD removalPhosphate removalAmmonia removalMaximum power density/voltage/currentReference
1. Swine slurry COD- 411–854 mg/L
TN-63 ± 7.5 mg/L
NH4+-N-40 ± 5.3 mg/L
TP -8.9 ± 2.1 mg/L
Reactive phosphorus (RP)- 6.2 ± 1.5 mg/L 
Alum sludge-based constructed wetland incorporating microbial fuel cell technology 1.1 ± 0.09 L, packing granular graphite anode (diameter 8–13 mm, initial porosity of 0.38) 1.1 ± 0.09 L, packing granular graphite cathode (diameter 8–13 mm, initial porosity of 0.38) Glass wool 1day 80% 85% 75% 0.268 W/m3 Doherty et al. (2015b)  
Swine wastewater COD-583 ± 92 mg/L
TN- 63 ±7.5 mg/L
NH4+-N-40 ± 5.3 mg/L
TP -8.9 ± 2.1 mg/L
PO4-P-6.2 ± 1.5 mg/L 
Constructed wetland -MFC Graphite granule with graphite rod anode Graphite granule with graphite rod cathode Glass wool 1 day 64 ± 4.6% PO4-P-90 ±2.2%
TP- 85 ± 4.0% 
NH4+-N-75 ± 3.1%
TN- 58 ± 3.1% 
0.276 W/m3 Doherty et al. (2015a)  
Municipal wastewater NH4+-N-21.3 ± 7.5 mg/L
TP-10.1 ± 3.6 mg/L 
MFC-based horizontal flow constructed wetland (Phragmites australis and Chrysopogon zizanioidesAluminium plate anode Aluminium plate cathode – – 80–100% ≥93% 55 t-92% 38.6 mW/m2 Saeed et al. (2022)  
Synthetic wastewater COD-200 mg/L, NO3N-40–80 mg/L, TP -4–8 mg/L Pyrite-based constructed wetland-microbial fuel cell (PCW-MFC) (Canna indica plant) Carbon fiber felts anode (12 cm in diameter, 1 mm in thickness) Carbon fiber felts cathode (12 cm in diameter, 1 mm in thickness) – 6 h 71.9 ± 3.6% TP-89.2 ± 2.7% NO3-N -67.5 ± 4.4% 2.67 mW/m2 Ge et al. (2020)  
Synthetic domestic wastewater NH3-N-25 mg/L NO2–N-0.1 mg/L,
NO3–N-0.5 mg/L,
organicN-15 mg/L
TN-40.6 mg/L
PO43−-P-4 mg/L
P3O105—P-1 mg/L,
TP-5 mg/L.
COD- 50–360 mg/L 
Constructed wetland-MFC (Canna indicaCarbon fiber brush anode Graphite plate cathode – 1.5 day – – TN- 90.30–91.46% 3.25 mW/m3 Wang et al. (2019c)  
Synthetic wastewater COD-314.8 ± 13 mg/L Up-flow constructed wetland-MFC (UFCW-MFC) (Typha latifoliaCarbon felt anode (total surface area 280 cm2Carbon felt cathode (total surface area 280 cm2– 1 day 100% – 91% 6.12 mW/m2 Oon et al. (2015)  
Secondary effluent from WWTP -synthetic WW COD-58.0 ± 2.2 mg/L,
TN-14.7 ± 1.5 mg/L,
NH4+-N-5.6 ± 1.1 mg/L
NO3-N-10.8 ± 1.4 mg/L 
Constructed wetland -MFC (corncobs were added to enhance the performance) Graphite plate anode (200 × 100 × 8 mm) Graphite plate cathode (200 × 100 × 8 mm) – 48 h 89.9% – NH4+-N-99.7%
NO3N- 100% 
1.92 mW/m2 Tao et al. (2022)  
Synthetic wastewater COD-150 mg/L,
NH4+-N-30 mg/L 
Tidal flow constructed wetland – MFC (TFCW-MFC) (Canna indica) Layer of Activated carbon granules and graphite felt (20 cm length × 10 cm width × 0.6 cm thickness) Carbon felt (14 cm outer diameter × 7 cm inner diameter × 0.6 cm thickness) – 7 Days >85% – TN- 52.89 ± 3.16% – Xu et al. (2021)  
Swine wastewater TCOD-73,828 ± 1,804 mg/L
SCOD-43,489 ± 1,146 mg/L
T-N-5,152 ± 266 mg/L
TAN-4,199 ± 27 mg/L
T-P -818 ± 19 mg/L 
Anaerobic digestor-MFC (3 identical air cathode MFCs) 320 mL, carbon felt anode Carbon cloth coated with a Pt catalyst (0.5 mg/cm2) cathode Nafion NAF NR212 – – – TAN- 77.5% 33 mW/m2 Kim et al. (2015)  
10 slaughterhouses wastewater COD-980–1,000 mg/L
NH4+-150–250 mg/L
NO3-15–20 mg/L
NO2-6–12 mg/L
Electrical conductivity (EC)- 920–1,280 μS/cm
pH – 6.3–7.1 
Microbial fuel cell, aerobic bioreactor, and anoxic bioreactor (MFC-AB-ANB) Uncoated plane graphite rod (effective surface area of 185.35 cm2Graphite granules (specific surface of 0.0832 m2 /g, and granular size diameter range of 2–4 mm) CEM (CMI- 7000 s) – 99% – 99.3% 162.55 mW/m2 Mohammed & Ismail (2018)  
11 Municipal wastewater COD-266.7 mg/L
NH4+-N-52.3 mg/L
PO43—P-6.2 mg/L 
Integrated photo bio-electrochemical system (Microbial fuel cell inside an algal bioreactor- Pseudokirchneriella subcapitata∼300 mL, 20 cm long carbon brush anode Layer of carbon cloth with Pt/C as catalysts cathode CEM, Ultrex CMI7000 12.5 h 92.4% 82.3% 98.6% 2.2 ± 0.2 W/m3 Xiao et al. (2012)  
12 Synthetic wastewater NaAc- 600 mg/L
NO3 − 95.0 mg/L 
MFC coupled with up-flow denitrification biofilter (BF) Graphite particle filter as bioanode Air cathode made of stainless steel – 24 h 87.50–90.86% – denitrification efficiency - 89.31–98.60% 0.48 mA Li et al. (2021b)  
13 Synthetic wastewater COD-1,505.61 ± 681.54 mg/L
NH4+-21.72 ± 7.99 mg/L
Phosphate-17.13 ± 5.77 mg/L 
Algal (Chlorella vulgaris) assisted constructed wetland (Canna indica)-MFC integrated with sand filter 600 mL, Graphite granules anode 750 mL, Carbon felt cathode Earthen membrane 5 days 96.37 ± 2.6% 69.03 ± 10.14% 85.14 ± 10.73% 33.14 mWm−3 Gupta et al. (2021)  
14 Domestic wastewater NH3-N-32 ± 4.28 mg/L
SCOD-1,080 ± 160 mg/L 
MFC-MBR Graphite brush anode (2.5 cm diameter × 2.5 cm length) Conductive UF membranes biocathodes prepared by dispersing multiwalled carbon nanotubes (MCNTs) (specific surface area of 117 m2/g) – 2–3 days SCOD-97.3 ± 1.1% – 97.3 ± 1.6% 0.38 W/m2 Malaeb et al. (2013)  
Platinum-based MCNT/polyester UF membrane cathode – 2–3 days 96.9 ± 0.6% – 95.2 ± 2.9% 0.82 W/m2 
15 Domestic wastewater CODtotal 323 mg/L
Ammonia 41 mg/L
Sulphate 102 mg/L
Orthophosphate9 mg/L 
Horizontal subsurface constructed wetland 20 cylindrical graphite rods wrapped in stainless steel (1 cm length and 0.5 cm diameter each) 20 cylindrical graphite rods wrapped in stainless steel (1 cm length and 0.5 cm diameter each) – 2.6 days 61% – 58% 36 mW/m2 Corbella et al. (2015)  

Constructed wetland treatment systems are naturally aerobic near the surface, which is suitable for the cathode reaction and are anaerobic as depth increases, providing suitable conditions for anode reactions (Doherty et al. 2015b). A 99.7% removal of ammonia was reported in constructed wetland–MFC with corncobs to enhance the performance (Tao et al. 2022). In these systems, nitrogen removal can take place by oxidation by nitrifiers combined with aerobic denitrification, bio-electrochemical oxidation, reduction or by ammonia volatilization (Xu et al. 2021). Many studies have utilized constructed wetland-MFC-integrated systems for nutrient removal. The schematic representation of a constructed wetland-MFC-integrated system is given in Figure 3(d). Canna indica, Phragmites australis, Chrysopogon zizanioides and Typha latifolia are used as plants in different constructed wetland-MFC-integrated systems (Doherty et al. 2015a; Lu et al. 2015; Oon et al. 2015; Ge et al. 2020; Saeed et al. 2022). A study conducted by Doherty et al. (2015b) with different configurations on swine slurry in constructed wetland–MFC showed an efficiency of about 80, 85, and 75% for COD, phosphorus and ammonia removal, respectively. This study also suggested that, by varying the inflow conditions, the efficiency can be increased. Wang et al. (2019c) was able to achieve a TN removal efficiency of 91.46% in a constructed wetland–MFC while treating synthetic domestic wastewater. Ge et al. (2020) reported that compared with the traditional constructed wetland–MFC system, the pyrite-based constructed wetland–MFC can give higher removal efficiencies under similar conditions since pyrite can enhance the N and P removal efficiency along with bioelectricity generation treating synthetic wastewater. An up-flow constructed wetland–MFC system using Typha latifolia has been reported to achieve 91% removal of NH4+-N while treating synthetic wastewater (Oon et al. 2015).

The tests conducted by Pepè Sciarria et al. (2019) coupling microbial electrochemical technologies with crystallization process gave approximately 90% overall phosphate reduction efficiency. The system consisted of an MFC followed by a precipitation process. The removal efficiency of this MFC system was 10–15% higher than microbial electrolysis cells (Pepè Sciarria et al. 2019). Complete nitrate removal was reported by using an integrated system with MFC, an aerobic bioreactor, and an anoxic bioreactor (Mohammed & Ismail 2018). Compared to a biofilter working alone to treat municipal sewage with a denitrification efficiency of 71.34%, a higher denitrification efficiency of 89.31% was reported when MFC was coupled with an up-flow denitrification biofilter (Li et al. 2021). Nutrient removal from nitrogen-rich swine wastewater was studied using an anaerobic digestor-MFC-integrated system to overcome low COD removal efficiency due to high TAN in the anaerobic digestor (Kim et al. 2015). An MFC–membrane bioreactor system was reported to have an ammonia removal efficiency of 97.3% while treating domestic wastewater (Malaeb et al. 2013).

Recovering nutrients from wastewater is a promising approach with an economic benefit. To achieve high removal and recovery efficiency, the operation at optimum conditions for different parameters affecting the overall MFC performance is required (Sivakumar 2021). Temperature, pH, electrodes, membrane, organic loading rate (OLR), hydraulic retention time (HRT), light intensity, light and dark cycles, initial nutrient concentration, dissolved oxygen concentration, and resistance are some of the important factors that affect the performance of MFCs used for nutrient removal and recovery. These factors are discussed here.

Temperature

A higher operating temperature can increase the microbial activity which can improve the reaction kinetics, mass transfer, coulombic efficiency, and power density (Kusmayadi et al. 2020). Increasing the electrolyte temperature from 37 to 45 °C can increase the COD removal efficiency and can result in higher voltage output (Anam et al. 2020). In a catalyst and mediator less dual-chamber MFC, the maximum voltage and current intensity was obtained at 35°C compared to 15, 20, 25, 30, and 40°C, along with NH3, NH4+, dissolved phosphorus, and phosphorus particulate removal of 73.22, 69.43, 31.18, and 72.45% respectively (Mansoorian 2016). In a study conducted by varying the temperature of microalgae-based MFC, maximum oxygen production and ammonium removal efficiency of 99.6% were obtained at 27°C, by enhancing both anode bacterial and cathode microalgae metabolisms compared to 19 and 35°C (Kakarla & Min 2019). Exposure to a higher temperature above the mesophilic range can cause cell damage to anaerobic bacteria (Anam et al. 2020).

pH

In an MFC, the microbial activity, precipitation of nutrients and growth of microalgae are all directly dependent on the pH. Microbial growth in an anode chamber is affected by extreme pH values. An unstable supply of electrons, protons and oxygen can affect the pH of the system resulting in physical ammonium loss and organic matter loss, and disrupt the physiology of the cell (Kusmayadi et al. 2020). A neutral pH is considered as optimum for maximum power generation. A pH between 6.5–7.0 is best for the microbial growth in the anaerobic chamber (Mansoorian 2016). An acidic pH or alkaline pH of anolyte shows a lower COD removal efficiency (Anam et al. 2020). The nutrient precipitation in the form of struvite requires a pH range of 8.0–8.4 in the cathode chamber (Ye et al. 2019c). The traditional dual-chambered MFC is capable of maintaining different pH values in two chambers to attain optimum activities in individual chambers. Single-chambered MFCs do not have this capability which makes dual-chambered MFC more efficient in nutrient removal (ElMekawy et al. 2013).

Electrodes

The bio-electrochemical reactions usually take place on the surface of the electrodes and hence the selection of electrodes is very important. Electrodes that are used as anode and cathode should have chemical stability, biocompatibility, high conductivity, large potential range, and a reproducible surface (Jain et al. 2015; Jayashree et al. 2019). The cost of an electrode is an important factor for nutrient removal with MFCs. Several types of cathodes and anodes have been used by different researchers in their studies. They can be classified into mainly two groups as metal-based electrodes and carbon-based electrodes. Carbon-based electrodes were found to be more efficient in energy production and more biocompatible compared to metal-based electrodes (Zhuang et al. 2012; Shahid et al. 2021b). Metal-based electrodes have more conductivity but less surface area (Shahid et al. 2021a). The composite of these carbon-based and metal-based electrodes can enhance efficiency much more. Optimum spacing depends on the design configuration, type of substrate and oxygen permeability of the membrane (Arun et al. 2020). Giving pretreatments such as heat treatment and silanization treatment can improve the performance of electrodes (Shahid et al. 2021b). A study conducted by Huggins et al. (2016) on industrial wastewater, used a biochar-based electrode that was able to remove 95% COD. A study by Shahid et al. (2021b) showed that carbon-based APTES pretreated electrodes can achieve 99 and 98% total phosphorus and ammonia removal efficiency in a microbial nutrient recovery cell while treating municipal wastewater. The coulombic efficiency can be increased by increasing the electrode surface area per reactor volume. This also increases anode biofilm growth (Bose et al. 2018). It has been reported that platinum-based carbon cloth gives approximately 65% higher power than a platinum-free carbon cloth cathode (Santoro et al. 2013). A complete nitrate removal was achieved with a biocathode containing seawater bacteria (Samrat et al. 2018).

Membrane

The transfer of cations from anode to cathode takes place through the membrane due to the concentration gradient. Different membranes such as CEM, AEM, bipolar membrane and ceramic membrane salt bridge have been used in MFCs. The membranes which can conduct protons and prevent fuel crossover are ideal membranes for MFCs (Ramirez-Nava et al. 2021). The CEM increases the pH, which further helps in nutrient precipitation in the cathode chamber. Nazia et al. (2020) synthesized a new cost-effective ionically crosslinked nanocomposite membrane made up of cationic aniline-treated polysulfone (APSf) doped with an anionic sulfonated multiwalled carbon nanotube (SMWCNT) to lower the oxygen crossover and enhance the chemical, tensile and thermal stabilities. This membrane was able to produce a power density of 304.2 mW/m2, which was higher than the power density of 197 mW/m2 with Nafion 117, while treating kitchen wastewater. Nafion and Ultrex membranes are commonly used in MFC studies (Kumar et al. 2017). CEM shows more removal efficiency compared to nonwoven and forward osmosis membranes (FO) in nutrient recovery (Ye et al. 2019c).

Microorganisms

Anaerobic microorganisms present in the anode chamber play a vital role in removing organic matter present in wastewater (Saravanan et al. 2021). Certain bacteria can transfer electrons produced by the oxidation of organic matter directly to the anode without electron mediators. Anode biofilms are usually covered with microbial species of different shapes and sizes (Sharma et al. 2021). The bacterial species affects the performance of MFC. The presence of methanogens in the system can decrease the coulombic efficiency and therefore pretreatments of inoculum to reduce methanogens can increase the power generation (Wang et al. 2019a; Raychaudhuri & Behera 2020). The electroactive organisms that present in the anode chamber include Geobacter, Rhodobacter and Turicibacter (Lu et al. 2015; Wang et al. 2019a). Sharma & Mutnuri (2019) while monitoring power generated from four different cultures of microorganisms found a higher maximum power density of 99 mW/ m2 from the pure culture of Proteus vulgaris. However, mixed bacterial culture showed better performance (Sharma & Mutnuri 2019). Even though several studies have shown an increase in COD removal with an increase in mixed liquor suspended solids (MLSS), the study conducted by Fazli et al. (2018) found the opposite. The microorganisms that belong to Proteobacteria are very helpful in nitrification and denitrification processes (Wang et al. 2019b). Certain bacteria belonging to Planctomycetes can remove nitrogenous pollutants by converting ammonia and nitrate into nitrogen. Nitrospira is considered very helpful in the nitrification process and Acinetobacter in the aerobic denitrification process (Xu et al. 2021). In photosynthetic microalgal–MFC the Proteobacteria concentration decreased with increase in algal biomass (Yang et al. 2018). The presence of Cyanobacteria in the cathode can produce reactive oxygen species that are beneficial for electricity generation (Wang et al. 2019a). The presence of microbial flora like Bacillus, Pseudomonas, Achromobacter, Acinetobacter, Flavobacterium, Azospirillum and Bdellovibrio in the MFC can remove nitrate and phosphate effectively (Shahid et al. 2021b). It has been reported that the presence of Zn(II) can reduce some functional genera in the microbial community, thereby reducing the nutrient removal efficiency of constructed wetland–MFC systems (Wang et al. 2020).

Organic loading rate

The wastewater characteristics and OLR influence the overall performance of an MFC. In a study conducted by Mansoorian (2016) using dairy wastewater, the maximum current density and power density were obtained at an OLR of 53.22 kg COD/m3.d and showed a decreasing effect above and below this value. The MFC performance highly depends upon the catalytic reaction of anaerobic bacteria for the substrate, electron transport to the anode, proton transfer to the cathode, and electron acceptor in the cathode chamber. These processes are highly dependent on the OLR. The removal of NH4+-N and PO43−-P in the anode chamber can be enhanced by increasing the OLR, as a specific COD:N:P ratio is required for growth of microorganisms in an anaerobic chamber. It has been concluded that the amount of nutrients needed for high-strength organic wastewater with COD >4,000 mg/L is higher, which increases nutrient removal in the anode chamber, reducing the struvite precipitation in the cathode chamber (Ye et al. 2019a). Therefore, the nutrient recovery rate decreases with increase in OLR. For this reason, dual-chamber MFC is a more suitable technology to recover nutrients from low-strength wastewater (Ye et al. 2019a). A higher OLR can also decrease coulombic efficiency due to a decrease or saturation in bacterial activity (Tamilarasan et al. 2017). At high OLRs, organic matter is taken up for bacterial growth instead of electricity generation and the electrons are accepted by receptors present in the solution itself (Mansoorian 2016). In addition, a higher COD value can cause membrane fouling, which adversely affects the performance of MFCs. In MNRC systems, high NH4+-N recovery was observed when bioavailable COD was higher and wastewater with high COD/NH4+ ratio was favorable for high current density production (El-Qelish & Mahmoud 2022).

Hydraulic retention time

Hydraulic retention time is an important parameter that influences the efficiency of the system. A study conducted by Ye et al. (2020b) on synthetic domestic wastewater with HRT ranging from 0.35 to 0.69 days concluded that a longer HRT produces maximum power density. However, the average nutrient removal efficiency was approximately the same in HRT range studied, which indicates that HRT can be reasonably reduced if economic nutrient recovery is the major objective (Ye et al. 2020b). In another study to understand the influence of HRT on bioelectricity production, Mansoorian (2016) changed HRT values between 2 and 8 days. The maximum power density of 621.13 mW/m2 was obtained at an HRT of 5 days. The increase in voltage when the HRT was increased from 3 to 5 days might be due to a longer contact time between the substrate and microorganisms. In an another study when the HRT was increased from 8 to 12 days in an algal biocathode MFC, TN and phosphorus removal efficiency increased from 82.9 and 86.3% to 95.5 and 96.4%, respectively (Yang et al. 2018). Therefore, increase in HRT can increase nutrient removal (Fazli et al. 2018; Nguyen & Min 2020). However, a longer HRT may limit power production and coulombic efficiency due to insufficient substrate (Ma et al. 2016).

Initial ammonia concentration

A higher concentration of ammonia in influents can cause cytotoxic impacts on the microbial community. The ammonia concentration can influence the activity of cytosolic enzymes and intracellular pH. A study by Ye et al. (2019b) suggested that there is a decrease in coulombic efficiency and power density as the influent ammonia concentration increased from 5 to 40 mg/L. However, the recovery rate of phosphate was insignificantly influenced at a wider influent ammonia concentration. The larger amount of ammonia conversely helps in the precipitation of phosphorus in the cathode chamber as struvite along with magnesium (Hirooka & Ichihashi 2013). Hiegemann et al. (2018) showed that the impact load of a total ammonia concentration greater than 800 mg/L can lead to the instant collapse of power generation due to the inhibition of exoelectrogenic biofilm. A study by Kim et al. (2015) demonstrated that the COD:TAN ratio is an important parameter in the anaerobic digestor–MFC system in terms of COD and nitrogen removals. Higher COD:TAN ratio is favorable to attain higher removal efficiency. An influent COD:TN ratio of ≥3 resulted in a TN removal of 90.30 to 91.46% in a constructed wetland–MFC system (Wang et al. 2019c). Complete removal of ammonia was observed in a photosynthetic MFC with an influent ammonia concentration of 50 mg/L within 210 h and the removal efficiencies decreased when ammonia concentration was increased further (Don & Babel 2021).

Dissolved oxygen concentration

An optimum level of dissolved oxygen (DO) should be maintained in the anode and cathode chambers to obtain the optimum performance of MFCs. In a study conducted by Ye et al. (2019c), the DO concentration in the anode chamber was kept below 0.02 mg/L to maintain the anaerobic condition, while a DO concentration around 6.22 mg/L was maintained in the cathode chamber by aeration to enhance the nutrient removal efficiency of MFC. In the case of algae-based MFCs, there was no need for external aeration, and the oxygen required for electron acceptance was produced by photosynthesis (Arun et al. 2020). The cathodic DO is a very important factor for nutrient removal. The efficiency of removal decreases as the DO concentration declined in the cathode chamber (Tao et al. 2014). High DO concentration conversely causes back diffusion to the anode chamber and decreases power density. Bazdar et al. (2018) reported a 53.4% decrease in power density when the DO concentration was increased from 7.8 to 9.5 mg/L in photosynthetic MFC using the microalgae Chlorella vulgaris.

Light intensity and light and dark cycle

There is optimum light intensity for algal-based MFCs. A long illumination period may increase oxygen production and thus electricity generation, but an extended illumination can decrease electricity production, since a dark period is required to maintain a healthy community of microorganisms (Xiao & He 2014). Bazdar et al. (2018) conducted tests under light intensities varying between 3,500 and 10,000 lx and a light/dark regime of 24/00, 12/12 and 16/8 h to investigate the performance of photosynthetic microalgae–MFCs. Their results suggest that light intensity between 5,000 and 6,500 lx is the optimum range for the growth of Chlorella vulgaris. Biomass growth is directly related to the nutrient removal in microalgae-based MFCs. In another study the optimum ammonia removal efficiency was obtained at 12/12 h light/dark cycles (Kakarla & Min 2019). With respect to the illumination characteristics, the energy production capacity also varies for different types of microalgae. Artificial light can increase the efficiency of MFC but it can increase the operational cost. For Chlamydomonas reinhardtii, power generation increased when red LED light was used (Lan et al. 2013). Increase in photon flux density also increases the ammonia removal rate and efficiency in photosynthetic MFCs. In an MFC with a microalgal cathode, illuminated with 92 μE/m2 s1 photon flux achieved complete ammonium removal within 96 h, while the cathode illuminated with 47, 27, or 13 μE/m2 s1 attained only 95, 63, or 70% ammonium removal, respectively (Kakarla & Min 2019).

Effect of resistance

In a fuel cell the maximum power transfer is achieved when loading resistance equals the internal resistance (Ieropoulos et al. 2008; Al-Mamun et al. 2017). Electrode spacing, electrode material, ionic strength and pH of the electrolyte, type of microbes and membrane are the main factors that can affect the internal resistance (Ieropoulos et al. 2005; Kumar et al. 2017). A study conducted by Huggins et al. (2016) using biochar electrodes and adsorption of nutrients to their surface suggested that biochar electrodes can reduce the internal resistance, while it can attain a removal efficiency of 88 and 73% for phosphate and ammonia, respectively. Reducing the electrode separation and increasing the DO concentration in the cathode can reduce the internal resistance and increase the power output in constructed wetland–MFC systems (Doherty et al. 2015a). The type of microorganisms and their metabolic products also affect the conductivity of the anolyte, thereby effecting the internal resistance (Ieropoulos et al. 2008).

Conventional nutrient removal/recovery techniques include precipitation, adsorption, and biological processes (Ye et al. 2020a; Rout et al. 2021). The biological processes face limitations in removing organic matter and nutrients simultaneously. The precipitation technique depends on the solution pH, while the adsorption technique needs effective desorption process to recover the adsorbed nutrients. Conversely, MFC is a self-sustainable and promising technique that can simultaneously produce electricity and treat wastewater (Logan et al. 2006; Wang et al. 2010). This technology can elevate the pH in the cathode chamber due to their inherent mechanism and without additional chemicals, which indicates their high economic feasibility to precipitate struvite (Ye et al. 2020a). The local pH near the cathode can precipitate nutrients, and ammonia can also be removed by air stripping. Modification of conventional MFCs with biocathode, algal photobioreactors, etc., can help to produce more value-added products such as biodiesel and pigments, simultaneously fixing CO2 and eliminating the cost of aeration in the cathode chamber (Arun et al. 2020). A recent study on ghee wastewater showed a COD removal efficiency of 90% for MFC that was significantly higher than that of conventional anaerobic treatment (73%), and biomass production in the anode chamber of MFC was 0.7 g/20 mL, which was much less than that in anaerobic treatment system (1.2 g/20 mL) (Elakkiya & Niju 2021).

While a number of studies showed the feasibility of MFCs for nutrient removal, most of these studies were conducted on a laboratory scale. To understand more about real applications, full-scale studies analyzing the relationship between various parameters are essential (Verma et al. 2021). Scale-up can be done by enlarging a single system or by stacking multiple reactors into one system (Ge & He 2016). But the modularized model shows more efficiency than simply enlarging the size of MFC (Ge & He 2016; Liang et al. 2018). A pilot-scale study with a 90 L stackable MFC treating brewery wastewater showed that MFCs can be employed for real wastewater treatment with zero energy input (Fitzgerald et al. 2015). A 1,000 L modularized MFC generated a maximum power density of 7–60 W/m3 while treating municipal wastewater (Liang et al. 2018). Only very few studies have reported in the scaled-up model study of MFC to remove nutrients. A study conducted by Ge & He (2016) on a 200 L modularized MFC system with 96 tubular MFCs gave 68% nitrogen removal efficiency. Even though air-cathode microbial electrochemical systems use energy for aeration, in a pilot-scale study it was found that the energy requirement was only about 12% of that of activated sludge process (He et al. 2019). In another pilot-scale study on an air-cathode MFC of 1,400 L liquid volume the system was able to achieve 9% columbic efficiency (Rossi et al. 2022).

Despite the advantages of MFCs, there are still many challenges that need to be resolved before successful commercial application. A better understanding of various parameters that affect the performance of MFCs is necessary to arrive at the optimum operating conditions. Since the coulombic efficiency is related to the internal resistance, which in turn depends upon various other factors, comprehensive studies focusing on improving the efficiency is required. The high cost of materials used in an MFC is one of the main limitations of this technology (Pepè Sciarria et al. 2019). However, a cost analysis by Ge & He (2016) indicates that the impact of cost factors can be reduced by applying this technology to an appropriate small treatment system with cost-effective methods. Membrane fouling, low power density, and high cost are the main issues faced during field applications. Microalgae-based systems are energy-consuming for their cultivation and harvesting (Gajda et al. 2015; Jaiswal et al. 2020). In the algal cathode chamber, another issue is the light penetration while there is the chance that the growth of microalgae can hinder the light reaching evenly affecting further growth of microalgae. The main advantages and constraints of MFCs for nutrient removal are summarized in Figure 4.

Figure 4

Advantages and constraints of MFCs in nutrient removal/recovery from wastewater.

Figure 4

Advantages and constraints of MFCs in nutrient removal/recovery from wastewater.

Close modal

The development of low resistant economic membranes and more efficient electrodes are needed for large-scale application. Even though the use of microalgae can reduce the aeration cost and carbon footprint, separation of algae from treated wastewater remains a challenge. Optimizing the arrangements of modules is crucial in the field-scale application (Ge & He 2016). Thus, to become a superior technology over current nutrient recovery techniques, future MFC research should focus on reducing the electrochemical energy loss, improving nutrient removal efficiency, and optimizing the operating conditions.

MFCs are bio-electrochemical systems in which microorganisms degrade organic matter in the wastewater to produce electrons simultaneously generating electricity and treating wastewater. Struvite, cattiite or vivianite precipitation, nutrient assimilation by microalgal biomass in the system, ammonia stripping, nitrification and denitrification are the different types of mechanisms through which MFCs remove and recover nitrogen and phosphate. The nutrient removal efficiency and power generation are affected by various parameters such as temperature, pH, type of electrode, type of membrane, OLR, HRT, light intensity and light and dark cycles, initial ammonium concentration, dissolved oxygen concentration, and resistance. For the large-scale application of MFCs for nutrient removal, high removal/recovery without compromising the electricity generation capacity has to be achieved at a low cost of construction. Full-scale field studies, and analysis of various process parameters affecting the nutrient recovery to establish relationships between them are required to develop efficient MFC systems for nutrient removal and recovery from different types of wastewaters.

All relevant data are included in the paper or its Supplementary Information.

The authors declare there is no conflict.

Aelterman
P.
,
Rabaey
K.
,
The Pham
H.
,
Boon
N.
&
Verstraete
W.
2006
Continuous electricity generation at high voltages and currents using stacked microbial fuel cells
.
Communications in Agricultural and Applied Biological Sciences
71
(
1
),
63
66
.
Al-Mamun
A.
,
Baawain
M. S.
,
Egger
F.
,
Al-Muhtaseb
A. H.
&
Ng
H. Y.
2017
Optimization of a baffled-reactor microbial fuel cell using autotrophic denitrifying bio-cathode for removing nitrogen and recovering electrical energy
.
Biochemical Engineering Journal
120
,
93
102
.
https://doi.org/10.1016/j.bej.2016.12.015
.
Anam
M.
,
Yousaf
S.
&
Ali
N.
2020
Comparative assessment of microbial-fuel-cell operating parameters
.
Journal of Environmental Engineering
146
(
9
),
1
7
.
https://doi.org/10.1061/(ASCE)EE.1943-7870.0001772
.
Arun
S.
,
Sinharoy
A.
,
Pakshirajan
K.
&
Lens
P. N. L.
2020
Algae based microbial fuel cells for wastewater treatment and recovery of value-added products
.
Renewable and Sustainable Energy Reviews
132
,
110041
.
https://doi.org/10.1016/j.rser.2020.110041
.
Asai
Y.
,
Miyahara
M.
,
Kouzuma
A.
&
Watanabe
K.
2017
Comparative evaluation of wastewater-treatment microbial fuel cells in terms of organics removal, waste-sludge production, and electricity generation
.
Bioresources and Bioprocessing
4
(
1
),
30
.
https://doi.org/10.1186/s40643-017-0163-7
Bazdar
E.
,
Roshandel
R.
,
Yaghmaei
S.
&
Mahdi
M.
2018
The effect of different light intensities and light/dark regimes on the performance of photosynthetic microalgae microbial fuel cell
.
Bioresource Technology
261
,
350
360
.
https://doi.org/10.1016/j.biortech.2018.04.026
.
Bolognesi
S.
,
Cecconet
D.
,
Callegari
A.
&
Capodaglio
A. G.
2021
Combined microalgal photobioreactor/microbial fuel cell system: performance analysis under different process conditions
.
Environmental Research
192
,
110263
.
https://doi.org/10.1016/j.envres.2020.110263
.
Bose
D.
,
Dhawan
H.
,
Kandpal
V.
,
Vijay
P.
&
Gopinath
M.
2018
Bioelectricity generation from sewage and wastewater treatment using two-chambered microbial fuel cell
.
International Journal of Energy Research
42
(
14
),
4335
4344
.
https://doi.org/10.1002/er.4172
.
Cabrera
J.
,
Dai
Y.
,
Irfan
M.
,
Li
Y.
,
Gallo
F.
,
Zhang
P.
,
Zong
Y.
&
Liu
X.
2022
Novel continuous up-flow MFC for treatment of produced water: flow rate effect, microbial community, and flow simulation
.
Chemosphere
289
,
133186
.
https://doi.org/10.1016/j.chemosphere.2021.133186
.
Chen
X.
,
Sun
D.
,
Zhang
X.
,
Liang
P.
&
Huang
X.
2015
Novel self-driven microbial nutrient recovery cell with simultaneous wastewater purification
.
Nature Publishing Group
5
,
15744
.
https://doi.org/10.1038/srep15744
Chen
X.
,
Zhou
H.
,
Zuo
K.
,
Zhou
Y.
,
Wang
Q.
,
Sun
D.
,
Gao
Y.
,
Liang
P.
,
Zhang
X.
,
Ren
Z. J.
&
Huang
X.
2017
Self-sustaining advanced wastewater purification and simultaneous in situ nutrient recovery in a novel bioelectrochemical system
.
Chemical Engineering Journal
330
,
692
697
.
https://doi.org/10.1016/j.cej.2017.07.130
.
Chen
Z.
,
Zhang
S.
&
Zhong
L.
2019
Simultaneous sulfide removal, nitrogen removal and electricity generation in a coupled microbial fuel cell system
.
Bioresource Technology
291
,
121888
.
https://doi.org/10.1016/j.biortech.2019.121888
.
Corbella
C.
,
Guivernau
M.
,
Viñas
M.
&
Puigagut
J.
2015
Operational, design and microbial aspects related to power production with microbial fuel cells implemented in constructed wetlands
.
Water Research
84
,
232
242
.
https://doi.org/10.1016/j.watres.2015.06.005
.
Cord-Ruwisch
R.
,
Law
Y.
&
Cheng
K. Y.
2011
Ammonium as a sustainable proton shuttle in bioelectrochemical systems
.
Bioresource Technology
102
(
20
),
9691
9696
.
https://doi.org/10.1016/j.biortech.2011.07.100
.
Do
M. H.
,
Ngo
H. H.
,
Guo
W. S.
,
Liu
Y.
,
Chang
S. W.
,
Nguyen
D. D.
,
Nghiem
L. D.
&
Ni
B. J.
2018
Challenges in the application of microbial fuel cells to wastewater treatment and energy production: a mini review
.
Science of the Total Environment
639
,
910
920
.
https://doi.org/10.1016/j.scitotenv.2018.05.136
.
Doherty
L.
,
Zhao
X.
,
Zhao
Y.
&
Wang
W.
2015a
The effects of electrode spacing and flow direction on the performance of microbial fuel cell-constructed wetland
.
Ecological Engineering
79
,
8
14
.
https://doi.org/10.1016/j.ecoleng.2015.03.004
.
Doherty
L.
,
Zhao
Y.
,
Zhao
X.
&
Wang
W.
2015b
Nutrient and organics removal from swine slurry with simultaneous electricity generation in an alum sludge-based constructed wetland incorporating microbial fuel cell technology
.
Chemical Engineering Journal
266
(
610
),
74
81
.
https://doi.org/10.1016/j.cej.2014.12.063
.
Don
C. D. Y. Y. A.
&
Babel
S.
2021
Effects of ammonium concentration in the catholyte on electricity and algal biomass generation in a photosynthetic microbial fuel cell treating wastewater
.
Bioresource Technology Reports
16
,
100867
.
https://doi.org/10.1016/j.biteb.2021.100867
.
Elmaadawy
K.
,
Hu
J.
,
Guo
S.
,
Hou
H.
,
Xu
J.
,
Wang
D.
,
Liang
T.
,
Yang
J.
,
Liang
S.
,
Xiao
K.
&
Liu
B.
2020
Enhanced treatment of landfill leachate with cathodic algal biofilm and oxygen-consuming unit in a hybrid microbial fuel cell system
.
Bioresource Technology
310
,
123420
.
https://doi.org/10.1016/j.biortech.2020.123420
.
ElMekawy
A.
,
Hegab
H. M.
,
Dominguez-Benetton
X.
&
Pant
D.
2013
Internal resistance of microfluidic microbial fuel cell: challenges and potential opportunities
.
Bioresource Technology
142
,
672
682
.
https://doi.org/10.1016/j.biortech.2013.05.061
.
El-Qelish
M.
&
Mahmoud
M.
2022
Overcoming organic matter limitation enables high nutrient recovery from sewage sludge reject water in a self-powered microbial nutrient recovery cell
.
Science of the Total Environment
802
,
149851
.
https://doi.org/10.1016/j.scitotenv.2021.149851
.
Fazli
N.
,
Mutamim
N. S. A.
,
Jafri
N. M. A.
&
Ramli
N. A. M.
2018
Microbial fuel cell (MFC) in treating spent caustic wastewater: varies in hydraulic retention time (HRT) and mixed liquor suspended solid (MLSS)
.
Journal of Environmental Chemical Engineering
6
(
4
),
4339
4346
.
https://doi.org/10.1016/j.jece.2018.05.059
.
Fitzgerald
L. A.
,
Petersen
E. R.
,
Gross
B. J.
,
Soto
C. M.
,
Ringeisen
B. R.
,
El-Naggar
M. Y.
,
Biffinger
J. C.
,
Dong
Y.
,
Qu
Y.
,
He
W.
,
Du
Y.
,
Liu
J.
,
Han
X.
&
Feng
Y.
2015
A 90-liter stackable baffled microbial fuel cell for brewery wastewater treatment based on energy self-sufficient mode
.
Bioresource Technology
195
(
1
),
66
72
.
http://dx.doi.org/10.1016/j.biortech.2015.06.026
.
Gajda
I.
,
Greenman
J.
,
Melhuish
C.
&
Ieropoulos
I.
2015
Self-sustainable electricity production from algae grown in a microbial fuel cell system
.
Biomass and Bioenergy
82
,
87
93
.
https://doi.org/10.1016/j.biombioe.2015.05.017
.
Ge
Z.
&
He
Z.
2016
Long-term performance of a 200 liter modularized microbial fuel cell system treating municipal wastewater: treatment, energy, and cost
.
Environmental Science: Water Research and Technology
2
(
2
),
274
281
.
https://doi.org/10.1039/c6ew00020 g
.
Ge
X.
,
Cao
X.
,
Song
X.
,
Wang
Y.
,
Si
Z.
,
Zhao
Y.
,
Wang
W.
&
Tesfahunegn
A. A.
2020
Bioenergy generation and simultaneous nitrate and phosphorus removal in a pyrite-based constructed wetland-microbial fuel cell
.
Bioresource Technology
296
,
122350
.
https://doi.org/10.1016/j.biortech.2019.122350
.
Gielen
D.
,
Boshell
F.
,
Saygin
D.
,
Bazilian
M. D.
,
Wagner
N.
&
Gorini
R.
2019
The role of renewable energy in the global energy transformation
.
Energy Strategy Reviews
24
,
38
50
.
https://doi.org/10.1016/j.esr.2019.01.006
.
Gujjala
L. K. S.
,
Dutta
D.
,
Sharma
P.
,
Kundu
D.
,
Vo
D. V. N.
&
Kumar
S.
2022
A state-of-the-art review on microbial desalination cells
.
Chemosphere
288
(
1
),
132386
.
https://doi.org/10.1016/j.chemosphere.2021.132386
.
Gupta
S.
,
Nayak
A.
,
Roy
C.
&
Yadav
A. K.
2021
An algal assisted constructed wetland-microbial fuel cell integrated with sand filter for efficient wastewater treatment and electricity production
.
Chemosphere
263
,
128132
.
https://doi.org/10.1016/j.chemosphere.2020.128132
.
Gurung
A.
&
Oh
S. E.
2012
The performance of serially and parallelly connected microbial fuel cells
.
Energy Sources, Part A: Recovery, Utilization and Environmental Effects
34
(
17
),
1591
1598
.
https://doi.org/10.1080/15567036.2011.629277
.
He
Z.
,
Wagner
N.
,
Minteer
S. D.
&
Angenent
L. T.
2006
An upflow microbial fuel cell with an interior cathode: assessment of the internal resistance by impedance spectroscopy
.
Environmental Science and Technology
40
(
17
),
5212
5217
.
https://doi.org/10.1021/es060394f
.
He
L.
,
Du
P.
,
Chen
Y.
,
Lu
H.
,
Cheng
X.
,
Chang
B.
&
Wang
Z.
2017
Advances in microbial fuel cells for wastewater treatment
.
Renewable and Sustainable Energy Reviews
71
,
388
403
.
https://doi.org/10.1016/j.rser.2016.12.069
.
He
W.
,
Dong
Y.
,
Li
C.
,
Han
X.
,
Liu
G.
,
Liu
J.
&
Feng
Y.
2019
Field tests of cubic-meter scale microbial electrochemical system in a municipal wastewater treatment plant
.
Water Research
155
,
372
380
.
https://doi.org/10.1016/j.watres.2019.01.062
.
Hiegemann
H.
,
Lübken
M.
,
Schulte
P.
,
Schmelz
K. G.
,
Gredigk-Hoffmann
S.
&
Wichern
M.
2018
Inhibition of microbial fuel cell operation for municipal wastewater treatment by impact loads of free ammonia in bench- and 45 L-scale
.
Science of the Total Environment
624
,
34
39
.
https://doi.org/10.1016/j.scitotenv.2017.12.072
.
Hirooka
K.
&
Ichihashi
O.
2013
Phosphorus recovery from artificial wastewater by microbial fuel cell and its effect on power generation
.
Bioresource Technology
137
,
368
375
.
https://doi.org/10.1016/j.biortech.2013.03.067
.
Huang
J.
,
Yang
P.
,
Guo
Y.
&
Zhang
K.
2011
Electricity generation during wastewater treatment: an approach using an AFB-MFC for alcohol distillery wastewater
.
Desalination
276
(
1–3
),
373
378
.
https://doi.org/10.1016/j.desal.2011.03.077
.
Huggins
T. M.
,
Latorre
A.
,
Biffinger
J. C.
&
Ren
Z. J.
2016
Biochar based microbial fuel cell for enhanced wastewater treatment and nutrient recovery
.
Sustainability
8
(
2
),
1
10
.
https://doi.org/10.3390/su8020169
.
Ichihashi
O.
&
Hirooka
K.
2012
Removal and recovery of phosphorus as struvite from swine wastewater using microbial fuel cell
.
Bioresource Technology
114
,
303
307
.
https://doi.org/10.1016/j.biortech.2012.02.124
.
Ieropoulos
I. A.
,
Greenman
J.
,
Melhuish
C.
&
Hart
J.
2005
Comparative study of three types of microbial fuel cell
.
Enzyme and Microbial Technology
37
(
2
),
238
245
.
https://doi.org/10.1016/j.enzmictec.2005.03.006
.
Ieropoulos
I.
,
Greenman
J.
&
Melhuish
C.
2008
Microbial fuel cells based on carbon veil electrodes: stack configuration and scalability
.
International Journal of Energy Research
32
(
13
),
1228
1240
.
https://doi.org/10.1002/er.1419
.
Jain
R.
,
Tiwari
D. C.
,
Sharma
S.
&
Mishra
P.
2015
Efficiency and stability of carbon cloth electrodes for electricity production from different types of waste water using dual chamber microbial fuel cell
.
Journal of Scientific and Industrial Research
74
(
5
),
308
314
.
Jaiswal
K. K.
,
Kumar
V.
,
Vlaskin
M. S.
,
Sharma
N.
,
Rautela
I.
,
Nanda
M.
,
Arora
N.
,
Singh
A.
&
Chauhan
P. K.
2020
Microalgae fuel cell for wastewater treatment: recent advances and challenges
.
Journal of Water Process Engineering
38
,
101549
.
https://doi.org/10.1016/j.jwpe.2020.101549
.
Jayashree
S.
,
Ramesh
S. T.
,
Lavanya
A.
,
Gandhimathi
R.
&
Nidheesh
P. V.
2019
Wastewater treatment by microbial fuel cell coupled with peroxicoagulation process
.
Clean Technologies and Environmental Policy
21
(
10
),
2033
2045
.
https://doi.org/10.1007/s10098-019-01759-0
.
Jiang
Q.
,
Song
X.
,
Liu
J.
,
Shao
Y.
&
Feng
Y.
2019
Enhanced nutrients enrichment and removal from eutrophic water using a self-sustaining in situ photomicrobial nutrients recovery cell (PNRC)
.
Water Research
167
,
115097
.
https://doi.org/10.1016/j.watres.2019.115097
.
Kelly
P. T.
&
He
Z.
2014
Nutrients removal and recovery in bioelectrochemical systems: a review
.
Bioresource Technology
153
,
351
360
.
https://doi.org/10.1016/j.biortech.2013.12.046
.
Kim
T.
,
An
J.
,
Jang
J. K.
&
Chang
I. S.
2015
Coupling of anaerobic digester and microbial fuel cell for COD removal and ammonia recovery
.
Bioresource Technology
195
,
217
222
.
https://doi.org/10.1016/j.biortech.2015.06.009
.
Kumar
R.
&
Pal
P.
2015
Assessing the feasibility of N and P recovery by struvite precipitation from nutrient-rich wastewater: a review
.
Environmental Science and Pollution Research
22
(
22
),
17453
17464
.
https://doi.org/10.1007/s11356-015-5450-2
.
Kumar
R.
,
Singh
L.
&
Zularisam
A. W.
2017
Microbial fuel cells: types and applications
.
Waste Biomass Management – A Holistic Approach
367
384
.
https://doi.org/10.1007/978-3-319-49595-8_16
.
Kuntke
P.
,
Śmiech
K. M.
,
Bruning
H.
,
Zeeman
G.
,
Saakes
M.
,
Sleutels
T. H. J. A.
,
Hamelers
H. V. M.
&
Buisman
C. J. N.
2012
Ammonium recovery and energy production from urine by a microbial fuel cell
.
Water Research
46
(
8
),
2627
2636
.
https://doi.org/10.1016/j.watres.2012.02.025
.
Kusmayadi
A.
,
Leong
Y. K.
,
Yen
H. W.
,
Huang
C. Y.
,
Dong
C. d.
&
Chang
J. S.
2020
Microalgae-microbial fuel cell (mMFC): an integrated process for electricity generation, wastewater treatment, CO2 sequestration and biomass production
.
International Journal of Energy Research
44
(
12
),
9254
9265
.
https://doi.org/10.1002/er.5531
.
Lan
J. C. W.
,
Raman
K.
,
Huang
C. M.
&
Chang
C. M.
2013
The impact of monochromatic blue and red LED light upon performance of photo microbial fuel cells (PMFCs) using Chlamydomonas reinhardtii transformation F5 as biocatalyst
.
Biochemical Engineering Journal
78
,
39
43
.
https://doi.org/10.1016/j.bej.2013.02.007
.
Li
N.
,
Wan
Y.
&
Wang
X.
2020
Nutrient conversion and recovery from wastewater using electroactive bacteria
.
Science of the Total Environment
706
,
135690
.
https://doi.org/10.1016/j.scitotenv.2019.135690
Li
M.
,
Zhou
M.
,
Tian
X.
,
Tan
C.
&
Gu
T.
2021a
Enhanced bioenergy recovery and nutrient removal from swine wastewater using an airlift-type photosynthetic microbial fuel cell
.
Energy
226
,
120422
.
https://doi.org/10.1016/j.energy.2021.120422
.
Li
Z. L.
,
Zhu
Z. L.
,
Lin
X. Q.
,
Chen
F.
,
Li
X.
,
Liang
B.
,
Huang
C.
,
Zhang
Y. M.
,
Sun
K.
,
Zhou
A. N.
&
Wang
A. J.
2021b
Microbial fuel cell-upflow biofilter coupling system for deep denitrification and power recovery: efficiencies, bacterial succession and interactions
.
Environmental Research
196
,
110331
.
https://doi.org/10.1016/j.envres.2020.110331
Liang
P.
,
Duan
R.
,
Jiang
Y.
,
Zhang
X.
,
Qiu
Y.
&
Huang
X.
2018
One-year operation of 1000-L modularized microbial fuel cell for municipal wastewater treatment
.
Water Research
141
,
1
8
.
https://doi.org/10.1016/j.watres.2018.04.066
.
Littfinski
T.
,
Beckmann
J.
,
Gehring
T.
,
Stricker
M.
,
Nettmann
E.
,
Krimmler
S.
,
Murnleitner
E.
,
Lübken
M.
,
Pant
D.
&
Wichern
M.
2022
Model-based identification of biological and pH gradient driven removal pathways of total ammonia nitrogen in single-chamber microbial fuel cells
.
Chemical Engineering Journal
431
,
133987
.
https://doi.org/10.1016/j.cej.2021.133987
.
Liu
H.
,
Cheng
S.
&
Logan
B. E.
2005
Production of electricity from acetate or butyrate using a single-chamber microbial fuel cell – environmental science & technology (ACS publications)
.
Environmental Science & Technology
39
(
2
),
658
662
.
04. 04. https://doi.org/10.1021/es048927c
.
Liu
J.
,
Cheng
X.
,
Qi
X.
,
Li
N.
,
Tian
J.
,
Qiu
B.
,
Xu
K.
&
Qu
D.
2018
Recovery of phosphate from aqueous solutions via vivianite crystallization: thermodynamics and influence of pH
.
Chemical Engineering Journal
349
,
37
46
.
https://doi.org/10.1016/j.cej.2018.05.064
.
Logan
B. E.
,
Hamelers
B.
,
Rozendal
R.
,
Schröder
U.
,
Keller
J.
,
Freguia
S.
,
Aelterman
P.
,
Verstraete
W.
&
Rabaey
K.
2006
Critical review microbial fuel cells: methodology and technology
.
Environmental Science & Technology
40
(
17
),
5181
5192
.
http://pubs.acs.org/doi/abs/10.1021/es0605016
.
Lu
L.
,
Xing
D.
&
Ren
Z. J.
2015
Microbial community structure accompanied with electricity production in a constructed wetland plant microbial fuel cell
.
Bioresource Technology
195
,
115
121
.
https://doi.org/https://doi.org/10.1016/j.biortech.2015.05.098
.
Ma
D.
,
Jiang
Z. H.
,
Lay
C. H.
&
Zhou
D.
2016
Electricity generation from swine wastewater in microbial fuel cell: hydraulic reaction time effect
.
International Journal of Hydrogen Energy
41
(
46
),
21820
21826
.
https://doi.org/10.1016/j.ijhydene.2016.08.019
.
Malaeb
L.
,
Katuri
K. P.
,
Logan
B. E.
,
Maab
H.
,
Nunes
S. P.
&
Saikaly
P. E.
2013
A hybrid microbial fuel cell membrane bioreactor with a conductive ultrafiltration membrane biocathode for wastewater treatment
.
Environmental Science and Technology
47
(
20
),
11821
11828
.
https://doi.org/10.1021/es4030113
.
Mukherjee
A.
,
Zaveri
P.
,
Patel
R.
,
Shah
M. T.
&
Munshi
N. S.
2021
Optimization of microbial fuel cell process using a novel consortium for aromatic hydrocarbon bioremediation and bioelectricity generation
.
Journal of Environmental Management
298
,
113546
.
https://doi.org/10.1016/j.jenvman.2021.113546
.
Mustakeem
.
2015
Electrode materials for microbial fuel cells: nanomaterial approach
.
Materials for Renewable and Sustainable Energy
4
(
22
).
https://doi.org/10.1007/s40243-015-0063-8
.
Nazia
S.
,
Jegatheesan
V.
,
Bhargava
S. K.
&
Sundergopal
S.
2020
Microbial fuel cell–aided processing of kitchen wastewater using high-Performance nanocomposite membrane
.
Journal of Environmental Engineering
146
(
8
),
04020073
.
https://doi.org/10.1061/(asce)ee.1943-7870.0001717
.
Negi
R.
&
Chandel
M. K.
2021
Analysing water-energy-GHG nexus in a wastewater treatment plant of Mumbai Metropolitan Region, India
.
Environmental Research
196
,
110931
.
https://doi.org/10.1016/j.envres.2021.110931
.
Nguyen
H. T. H.
&
Min
B.
2020
Leachate treatment and electricity generation using an algae-cathode microbial fuel cell with continuous flow through the chambers in series
.
Science of the Total Environment
723
,
138054
.
https://doi.org/10.1016/j.scitotenv.2020.138054
.
Oon
Y. L.
,
Ong
S. A.
,
Ho
L. N.
,
Wong
Y. S.
,
Oon
Y. S.
,
Lehl
H. K.
&
Thung
W. E.
2015
Hybrid system up-flow constructed wetland integrated with microbial fuel cell for simultaneous wastewater treatment and electricity generation
.
Bioresource Technology
186
,
270
275
.
https://doi.org/10.1016/j.biortech.2015.03.014
.
Patel
A.
,
Mungray
A. A.
&
Mungray
A. K.
2020
Technologies for the recovery of nutrients, water and energy from human urine: a review
.
Chemosphere
259
,
127372
.
https://doi.org/10.1016/j.chemosphere.2020.127372
.
Paucar
N. E.
&
Sato
C.
2021
Microbial fuel cell for energy production, nutrient removal and recovery from wastewater: a review
.
Processes
9
.
https://doi.org/10.3390/pr9081318
Pepè Sciarria
T.
,
Vacca
G.
,
Tambone
F.
,
Trombino
L.
&
Adani
F.
2019
Nutrient recovery and energy production from digestate using microbial electrochemical technologies (METs)
.
Journal of Cleaner Production
208
,
1022
1029
.
https://doi.org/10.1016/j.jclepro.2018.10.152
.
Rahimnejad
M.
,
Ghoreyshi
A. A.
,
Najafpour
G. D.
,
Younesi
H.
&
Shakeri
M.
2012
A novel microbial fuel cell stack for continuous production of clean energy
.
International Journal of Hydrogen Energy
37
,
5992
6000
.
https://doi.org/10.1016/j.ijhydene.2011.12.154
.
Rahman
S.
,
Jafary
T.
,
Al-Mamun
A.
,
Baawain
M. S.
,
Choudhury
M. R.
,
Alhaimali
H.
,
Siddiqi
S. A.
,
Dhar
B. R.
,
Sana
A.
,
Lam
S. S.
,
Aghbashlo
M.
&
Tabatabaei
M.
2021
Towards upscaling microbial desalination cell technology: a comprehensive review on current challenges and future prospects
.
Journal of Cleaner Production
288
.
https://doi.org/10.1016/j.jclepro.2020.125597
.
Ramirez-Nava
J.
,
Martínez-Castrejón
M.
,
García-Mesino
R. L.
,
López-Díaz
J. A.
,
Talavera-Mendoza
O.
,
Sarmiento-Villagrana
A.
,
Rojano
F.
&
Hernández-Flores
G.
2021
The implications of membranes used as separators in microbial fuel cells
.
Membranes. MDPI
11
(
10
).
https://doi.org/10.3390/membranes11100738
.
Raychaudhuri
A.
&
Behera
M.
2020
Comparative evaluation of methanogenesis suppression methods in microbial fuel cell during rice mill wastewater treatment
.
Environmental Technology and Innovation
17
.
https://doi.org/10.1016/j.eti.2019.100509
.
Rossi
R.
,
Hur
A. Y.
,
Page
M. A.
,
Thomas
A. O. B.
,
Butkiewicz
J. J.
,
Jones
D. W.
,
Baek
G.
,
Saikaly
P. E.
,
Cropek
D. M.
&
Logan
B. E.
2022
Pilot scale microbial fuel cells using air cathodes for producing electricity while treating wastewater
.
Water Research
215
.
https://doi.org/10.1016/j.watres.2022.118208
.
Rout
P. R.
,
Shahid
M. K.
,
Dash
R. R.
,
Bhunia
P.
,
Liu
D.
,
Varjani
S.
,
Zhang
T. C.
&
Surampalli
R. Y.
2021
Nutrient removal from domestic wastewater: a comprehensive review on conventional and advanced technologies
.
Journal of Environmental Management
296
,
113246
.
https://doi.org/10.1016/j.jenvman.2021.113246
.
Rozendal
R. A.
,
Sleutels
T. H. J. A.
,
Hamelers
H. V. M.
&
Buisman
C. J. N.
2008
Effect of the type of ion exchange membrane on performance, ion transport, and pH in biocatalyzed electrolysis of wastewater
.
Water Science and Technology
57
,
1757
1762
.
https://doi.org/10.2166/wst.2008.043
.
Saeed
T.
,
Yadav
A. K.
&
Miah
M. J.
2022
Influence of electrodes and media saturation in horizontal flow wetlands employed for municipal sewage treatment: a comparative study
.
Environmental Technology & Innovation
25
,
102160
.
https://doi.org/10.1016/j.eti.2021.102160
.
Samrat
M. V. V. N.
,
Kesava Rao
K.
,
Ruggeri
B.
&
Tommasi
T.
2018
Denitrification of water in a microbial fuel cell (MFC) using seawater bacteria
.
Journal of Cleaner Production
178
,
449
456
.
https://doi.org/10.1016/j.jclepro.2017.12.221
.
Santoro
C.
,
Ieropoulos
I.
,
Greenman
J.
,
Cristiani
P.
,
Vadas
T.
,
Mackay
A.
&
Li
B.
2013
Power generation and contaminant removal in single chamber microbial fuel cells (SCMFCs) treating human urine
.
International Journal of Hydrogen Energy
38
(
26
),
11543
11551
.
https://doi.org/10.1016/j.ijhydene.2013.02.070
.
Santos
F. M.
&
Pires
J. C. M.
2018
Nutrient recovery from wastewaters by microalgae and its potential application as bio-char
.
Bioresource Technology
267
,
725
731
.
https://doi.org/10.1016/j.biortech.2018.07.119
.
Saravanan
A.
,
Kumar
P. S.
,
Srinivasan
S.
,
Jeevanantham
S.
,
Kamalesh
R.
&
Karishma
S.
2021
Sustainable strategy on microbial fuel cell to treat the wastewater for the production of green energy
.
Chemosphere
290
,
133295
.
https://doi.org/10.1016/j.chemosphere.2021.133295
.
Shahid
K.
,
Ramasamy
D. L.
,
Haapasaari
S.
,
Sillanpää
M.
&
Pihlajamäki
A.
2021a
Stainless steel and carbon brushes as high-performance anodes for energy production and nutrient recovery using the microbial nutrient recovery system
.
Energy
233
.
https://doi.org/10.1016/j.energy.2021.121213
Shahid
K.
,
Ramasamy
D. L.
&
Kaur
P.
2021b
Effect of modified anode on bioenergy harvesting and nutrients removal in a microbial nutrient recovery cell
.
Bioresource Technology
332
,
125077
.
https://doi.org/10.1016/j.biortech.2021.125077
Sharma
P.
&
Mutnuri
S.
2019
Nutrient recovery and microbial diversity in human urine fed microbial fuel cell
.
Water Science and Technology
79
(
4
),
718
730
.
https://doi.org/10.2166/wst.2019.089
.
Sharma
P.
,
Talekar
G. v.
&
Mutnuri
S.
2021
Demonstration of energy and nutrient recovery from urine by field-scale microbial fuel cell system
.
Process Biochemistry
101
,
89
98
.
https://doi.org/10.1016/j.procbio.2020.11.014
.
Sharma
R.
,
Mishra
A.
,
Pant
D.
&
Malaviya
P.
2022
Recent advances in microalgae-based remediation of industrial and non-industrial wastewaters with simultaneous recovery of value-added products
.
Bioresource Technology
344
,
126129
.
https://doi.org/10.1016/j.biortech.2021.126129
Sivakumar
D.
2021
Wastewater treatment and bioelectricity production in microbial fuel cell: salt bridge configurations
.
International Journal of Environmental Science and Technology
18
(
6
),
1379
1394
.
https://doi.org/10.1007/s13762-020-02864-0
.
Sun
D.
,
Gao
Y.
,
Hou
D.
,
Zuo
K.
,
Chen
X.
,
Liang
P.
,
Zhang
X.
,
Ren
Z. J.
&
Huang
X.
2018
Energy-neutral sustainable nutrient recovery incorporated with the wastewater purification process in an enlarged microbial nutrient recovery cell
.
Journal of Power Sources
384
,
160
164
.
https://doi.org/10.1016/j.jpowsour.2018.02.049
.
Tamilarasan
K.
,
Banu
J. R.
,
Jayashree
C.
,
Yogalakshmi
K. N.
&
Gokulakrishnan
K.
2017
Effect of organic loading rate on electricity generating potential of upflow anaerobic microbial fuel cell treating surgical cotton industry wastewater
.
Journal of Environmental Chemical Engineering
5
(
1
),
1021
1026
.
https://doi.org/10.1016/j.jece.2017.01.025
.
Tan
W. H.
,
Chong
S.
,
Fang
H. W.
,
Pan
K. L.
,
Mohamad
M.
,
Lim
J. W.
,
Tiong
T. J.
,
Chan
Y. J.
,
Huang
C. M.
&
Yang
T. C. K.
2021
Microbial fuel cell technology – a critical review on scale-up issues
.
Processes
9
(
6
).
https://doi.org/10.3390/pr9060985
Tao
X.
&
Chengwen
W.
2012
Energy consumption in wastewater treatment plants in China
.
World Congress on Water, Climate and Energy
.
Dublin, Ireland
.
1
6
.
Tao
Q.
,
Luo
J.
,
Zhou
J.
,
Zhou
S.
,
Liu
G.
&
Zhang
R.
2014
Effect of dissolved oxygen on nitrogen and phosphorus removal and electricity production in microbial fuel cell
.
Bioresource Technology
164
,
402
407
.
https://doi.org/10.1016/j.biortech.2014.05.002
.
Tao
Q.
,
Zhou
S.
,
Luo
J.
&
Yuan
J.
2015
Nutrient removal and electricity production from wastewater using microbial fuel cell technique
.
Desalination
365
,
92
98
.
https://doi.org/10.1016/j.desal.2015.02.021
.
Tao
M.
,
Jing
Z.
,
Tao
Z.
,
Luo
H.
,
Zuo
S.
&
Li
Y.-Y.
2022
Efficient nitrogen removal in microbial fuel cell – constructed wetland with corncobs addition for secondary effluent treatment
.
Journal of Cleaner Production
332
,
130108
.
https://doi.org/10.1016/j.jclepro.2021.130108
.
Varanasi
J. L.
,
Roy
S.
,
Pandit
S.
&
Das
D.
2015
Improvement of energy recovery from cellobiose by thermophillic dark fermentative hydrogen production followed by microbial fuel cell
.
International Journal of Hydrogen Energy
40
,
8311
8321
.
https://doi.org/10.1016/j.ijhydene.2015.04.124
.
Verma
P.
,
Daverey
A.
,
Kumar
A.
&
Arunachalam
K.
2021
Microbial fuel cell – A sustainable approach for simultaneous wastewater treatment and energy recovery
.
Journal of Water Process Engineering
40
.
https://doi.org/10.1016/j.jwpe.2020.101768
Wang
X.
,
Feng
Y.
,
Liu
J.
,
Lee
H.
,
Li
C.
,
Li
N.
&
Ren
N.
2010
Sequestration of CO2 discharged from anode by algal cathode in microbial carbon capture cells (MCCs)
.
Biosensors and Bioelectronics
25
(
12
),
2639
2643
.
https://doi.org/10.1016/j.bios.2010.04.036
.
Wang
Y.
,
Lin
Z.
,
Su
X.
,
Zhao
P.
,
Zhou
J.
,
He
Q.
&
Ai
H.
2019a
Cost-effective domestic wastewater treatment and bioenergy recovery in an immobilized microalgal-based photoautotrophic microbial fuel cell (PMFC)
.
Chemical Engineering Journal
372
,
956
965
.
https://doi.org/10.1016/j.cej.2019.05.004
.
Wang
X.
,
Tian
Y.
,
Liu
H.
,
Zhao
X.
&
Wu
Q.
2019c
Effects of influent COD/TN ratio on nitrogen removal in integrated constructed wetland–microbial fuel cell systems
.
Bioresource Technology
271
,
492
495
.
https://doi.org/10.1016/j.biortech.2018.09.039
.
Wang
Q.
,
Lv
R.
,
Rene
E. R.
,
Qi
X.
,
Hao
Q.
,
Du
Y.
,
Zhao
C.
,
Xu
F.
&
Kong
Q.
2020
Characterization of microbial community and resistance gene (CzcA) shifts in up-flow constructed wetlands-microbial fuel cell treating Zn (II) contaminated wastewater
.
Bioresource Technology
302
,
122867
.
https://doi.org/10.1016/j.biortech.2020.122867
Wicaksono
A.
,
Jeong
G.
&
Kang
D.
2017
Water, energy, and food nexus: review of global implementation and simulation model development
.
Water Policy
19
(
3
),
440
462
.
https://doi.org/10.2166/wp.2017.214.
Wu
L. C.
,
Chen
C. Y.
,
Lin
T. K.
,
Su
Y. Y.
&
Chung
Y. C.
2020
Highly efficient removal of Victoria blue R and bioelectricity generation from textile wastewater using a novel combined dual microbial fuel cell system
.
Chemosphere
258
.
2020.127326. https://doi.org/10.1016/j.chemosphere.2020.127326
.
Xiao
L.
&
He
Z.
2014
Applications and perspectives of phototrophic microorganisms for electricity generation from organic compounds in microbial fuel cells
.
Renewable and Sustainable Energy Reviews
37
,
550
559
.
https://doi.org/10.1016/j.rser.2014.05.066
.
Xiao
L.
,
Young
E. B.
,
Berges
J. A.
&
He
Z.
2012
Integrated photo-bioelectrochemical system for contaminants removal and bioenergy production
.
Environmental Science and Technology
46
(
20
),
11459
11466
.
https://doi.org/10.1021/es303144n
.
Xu
D.
,
Lin
L.
,
Xu
P.
,
Zhou
Y.
,
Xiao
E.
,
He
F.
&
Wu
Z.
2021
Effect of drained-flooded time ratio on ammonia nitrogen removal in a constructed wetland-microbial fuel cell system by tidal flow operation
.
Journal of Water Process Engineering
44
.
https://doi.org/10.1016/j.jwpe.2021.102450
Yadav
A. K.
,
Dash
P.
,
Mohanty
A.
,
Abbassi
R.
&
Mishra
B. K.
2012
Performance assessment of innovative constructed wetland-microbial fuel cell for electricity production and dye removal
.
Ecological Engineering
47
,
126
131
.
https://doi.org/10.1016/j.ecoleng.2012.06.029
.
Yang
Z.
,
Pei
H.
,
Hou
Q.
,
Jiang
L.
,
Zhang
L.
&
Nie
C.
2018
Algal biofilm-assisted microbial fuel cell to enhance domestic wastewater treatment: nutrient, organics removal and bioenergy production
.
Chemical Engineering Journal
332
,
277
285
.
https://doi.org/10.1016/j.cej.2017.09.096
.
Yang
Z.
,
Zhang
L.
,
Nie
C.
,
Hou
Q.
,
Zhang
S.
&
Pei
H.
2019
Multiple anodic chambers sharing an algal raceway pond to establish a photosynthetic microbial fuel cell stack: voltage boosting accompany wastewater treatment
.
Water Research
164
,
114955
.
https://doi.org/10.1016/j.watres.2019.114955
Ye
Y.
,
Ngo
H. H.
,
Guo
W.
,
Liu
Y.
,
Chang
S. W.
,
Nguyen
D. D.
,
Liang
H.
&
Wang
J.
2018
A critical review on ammonium recovery from wastewater for sustainable wastewater management
.
Bioresource Technology
268
,
749
758
.
https://doi.org/10.1016/j.biortech.2018.07.111
.
Ye
Y.
,
Ngo
H. H.
,
Guo
W.
,
Chang
S. W.
,
Nguyen
D. D.
,
Liu
Y.
,
Nghiem
L. D.
,
Zhang
X.
&
Wang
J.
2019a
Effect of organic loading rate on the recovery of nutrients and energy in a dual-chamber microbial fuel cell
.
Bioresource Technology
281
,
367
373
.
https://doi.org/10.1016/j.biortech.2019.02.108
.
Ye
Y.
,
Ngo
H. H.
,
Guo
W.
,
Chang
S. W.
,
Nguyen
D. D.
,
Liu
Y.
,
Ni
B. j.
&
Zhang
X.
2019b
Microbial fuel cell for nutrient recovery and electricity generation from municipal wastewater under different ammonium concentrations
.
Bioresource Technology
292
,
121992
.
https://doi.org/10.1016/j.biortech.2019.121992
.
Ye
Y.
,
Ngo
H. H.
,
Guo
W.
,
Liu
Y.
,
Chang
S. W.
,
Nguyen
D. D.
,
Ren
J.
,
Liu
Y.
&
Zhang
X.
2019c
Feasibility study on a double chamber microbial fuel cell for nutrient recovery from municipal wastewater
.
Chemical Engineering Journal
358
,
236
242
.
https://doi.org/10.1016/j.cej.2018.09.215
.
Ye
Y.
,
Ngo
H. H.
,
Guo
W.
,
Chang
S. W.
,
Nguyen
D. D.
,
Zhang
X.
,
Zhang
J.
&
Liang
S.
2020a
Nutrient recovery from wastewater: from technology to economy
.
Bioresource Technology Reports
11
.
https://doi.org/10.1016/j.biteb.2020.100425
Ye
Y.
,
Ngo
H. H.
,
Guo
W.
,
Chang
S. W.
,
Nguyen
D. D.
,
Zhang
X.
,
Zhang
S.
,
Luo
G.
&
Liu
Y.
2020b
Impacts of hydraulic retention time on a continuous flow mode dual-chamber microbial fuel cell for recovering nutrients from municipal wastewater
.
Science of the Total Environment
734
,
139220
.
https://doi.org/10.1016/j.scitotenv.2020.139220
.
Yetilmezsoy
K.
,
Ilhan
F.
,
Kocak
E.
&
Akbin
H. M.
2017
Feasibility of struvite recovery process for fertilizer industry: a study of financial and economic analysis
.
Journal of Cleaner Production
152
,
88
102
.
https://doi.org/10.1016/j.jclepro.2017.03.106
.
Zhang
F.
,
Li
J.
&
He
Z.
2014
A new method for nutrients removal and recovery from wastewater using a bioelectrochemical system
.
Bioresource Technology
166
,
630
634
.
https://doi.org/10.1016/j.biortech.2014.05.105
.
Zhao
F.
,
Harnisch
F.
,
Schröder
U.
,
Scholz
F.
,
Bogdanoff
P.
&
Herrmann
I.
2006
Challenges and constraints of using oxygen cathodes in microbial fuel cells
.
Environmental Science and Technology
40
(
17
),
5193
5199
.
https://doi.org/10.1021/es060332p
.
Zhuang
L.
,
Zheng
Y.
,
Zhou
S.
,
Yuan
Y.
,
Yuan
H.
&
Chen
Y.
2012
Scalable microbial fuel cell (MFC) stack for continuous real wastewater treatment
.
Bioresource Technology
106
,
82
88
.
https://doi.org/10.1016/j.biortech.2011.11.019
.
Zinadini
S.
,
Zinatizadeh
A. A.
,
Rahimi
M.
,
Vatanpour
V.
&
Bahrami
K.
2017
Energy recovery and hygienic water production from wastewater using an innovative integrated microbial fuel cell–membrane separation process
.
Energy
141
,
1350
1362
.
https://doi.org/10.1016/j.energy.2017.11.057
.
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