Abstract
The research aims to find out the reusability of jute stick charcoal (JSC) to remove Remazol Red (RR) from textile effluents. The JSC was characterized by scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy, and Fourier-transform infrared (FTIR) spectroscopy to analyze the morphology, functional groups, and chemical composition, respectively. The batch adsorption method was applied in this study, and it disclosed that dye uptake depends on various factors, namely, pH, contact time, adsorbent dose, and dye concentration. Notably, 93.12% of the dye was removed with the best removal efficiency at a pH of 1, an adsorbent dose of 0.6 g, and an equilibrium time of 120 min, where the adsorption occurred rapidly in the first 20 min. The Langmuir isotherm model successfully defined the adsorption phenomena, yielding an R2 value of 0.995. The kinetic experimental data followed the pseudo-second-order model (R2 = 0.999). The optimum adsorption parameters were implemented for the effluent obtained from a dye bath where a fabric sample (5 g) was dyed with RR, and 62.4% dye was removed. For the scaled application of JSC to a wastewater stream, the raw textile effluent was also treated, which resulted in 52.6% of dye removal. These results show that JSC is a promising adsorbent for treating textile wastewater.
HIGHLIGHTS
Adsorption of RR dye on JSC and characterization of JSC were studied.
The adsorption process is highly pH-specific (pH = 1).
Nearly 93.12% of the dye removal was observed at optimized conditions.
The experimental findings fit well with pseudo-second-order and Langmuir models.
The optimum conditions have been implemented on both the dyed sample fabric bath (62.4% removal) and actual raw textile effluent (52.6%).
INTRODUCTION
Dyes are the unsaturated organic compound that can impart colour to the substrate when adhered (Yagub et al. 2014). Before the invention of artificial chemical dyes in the latter part of the 19th century, natural dyes were the only means of colouration. After the development of synthetic dyes, the manufacturing of dyes grew significantly, leading to the greater consumption of dyes in different fields of life. This makes dyes an integral component of various industries like textile, leather, cosmetics, paper, food, electronics, etc. Among all the above-mentioned sectors, the textile industry accounts for the most considerable proportion of dye usage and emits a significant volume of effluent. According to an estimation, the textile industry releases about 200,000 tons of toxic waste into the water each year during dyeing and finishing (Ogugbue & Sawidis 2011). Dyes are carcinogenic in nature, so even a small quantity of dye (even below 1 ppm) discharged into waterways contaminates water sources (Daneshvar et al. 2003). Consistent with the literature, it is observed that the dyes and wastewater from textile industries cause harmful impacts on plants (Ghodake et al. 2009). Both natural and manufactured dyes can create water pollution, which is now a serious risk to the ecology and human beings (Alsukaibi 2022). These dyes accumulate in the food chain, disturbing the food web that consequently affects both aquatic and land environments. They are accountable for decreasing photosynthesis rate as they hinder the permeation of light deep into the water system, posing adverse effects on aquatic fauna and flora. They degrade water quality, causing skin soreness, respiratory issues, mental illness, vomiting, etc. Given this context, wastewater must be decontaminated before releasing it into the environment. Due to the complicated structures of aromatic compounds (resistance towards degradation) present in synthetic dyes, they are difficult to eliminate from wastewater (Ahmed et al. 2022).
To date, several wastewater removal processes, such as coagulation, filtration, photo-oxidation, chemical oxidation, advanced oxidation process, biodegradation, and many other methods, have been developed for dye removal from wastewater (Cai et al. 2017). However, it is obvious from the literature that both biological and chemical wastewater treatment methods find limited uses due to their high cost, low selectivity, and side product formation (in the form of sludge), which is another source of secondary pollution (Ghzal et al. 2023). Among the dye removal methods, adsorption is one of the preferable methods to others because of its simple methods, cheapness, high effectiveness, and lack of insensitivity to toxic substances (Foo & Hameed 2010; Zhu et al. 2019). In the adsorption process, choosing an appropriate adsorbent is the first and most important step. For the removal of different types of dyes, a variety of adsorbents have been reported in the literature as walnut wood, peels of orange, sugarcane bagasse, soy waste, and many more (Ghzal et al. 2023). However, in this study, we utilized jute stick charcoal (JSC) as an adsorbent, which is a cheap and abundant material in the South Asian region, and RR, a vinyl sulphone-grouped reactive dye, is very famous in the textile industry. The dye poses a nucleophilic addition reaction with cellulose fibres (since the percentage composition of cellulose is high in textile fibre) like cotton, viscose, etc. (Iqbal 2008).
To date, different kinds of adsorbents have been employed to adsorb RR dye, including O-carboxymethylchitosan-N-lauryl/γ-Fe2O3 magnetic nanoparticles (Demarchi et al. 2019), coconut shell-derived activated form of carbon (Saraswati & Sastrawidana 2021), rice husk ash (Costa & Paranhos 2019), chitosan (Kabir et al. 2014), etc. However, this paper is novel in the sense that this is the first-ever report on RR dye (anionic) removal using non-modified jute charcoal. Consistent with the literature, it is observed that Hossain et al. (2016) used treated jute stick powder for Levafix Red (LR) removal and reported 91% adsorption of dye from water. Nipa et al. (2019) worked on the removal of methylene blue dye by using jute stick powder. Furthermore, carboxylated carbon of jute stick was utilized to remove lead (Pb2+) (Aziz et al. 2019). Jute stick activated carbon was studied for three different dyes, i.e., acid red-1, reactive orange-16, and methylene blue (Ghosh et al. 2021). JSC has also been reported to remove methylene blue dye from water (Chakraborty et al. 2020), and it has demonstrated a notable adsorption capacity for Cr(VI), with a maximum adsorption capacity of 11.429 mg/g (Zaman et al. 2022). However, our research indicates that no research has still been conducted on RR dye removal using non-modified JSC, specifically under optimal experimental conditions, from wastewater from a dye bath of fabric samples dyed with the same dye and actual raw textile effluent. Furthermore, for the scaled application of JSC to a wastewater stream with a matrix of constituents, the raw textile effluent was also treated under optimized conditions. Given this context, this study aimed to explore the reusability of JSC for the removal of RR from textile effluent, which will promote sustainability, recycling, and waste management by replacing conventional wastewater treatment methods with effective and eco-friendly adsorption processes employing the use of JSC as an adsorbent.
MATERIALS AND METHODS
All reagents, chemicals, and apparatuses
RR (λmax = 518) was used in this study and obtained from Dystar Chemicals Ltd., Singapore. A single jersey knitted fabric was collected from the Fabric Engineering Lab of Textile Engineering College, Noakhali. The wetting agent, the sequestering agent, H2O2 (50%), and detergent (explained in the section ‘Pre-treatment and dyeing of the fabric sample’) were purchased from Officina 39, Italy. All other chemicals and reagents were purchased from the Taj Scientific Store, Chattogram. The apparatuses used in this study were a digital pH meter (Hanna, Romania), a mortar, an electronic balance (EHB, T-scale), a magnetic stirrer (MI0102003), a UV–vis spectrophotometer (CE Cecil 7400, UK), a Fourier-transform infrared spectrophotometer (L160000F, Spectrum Two FTIR Spectrometer), an oven drier (GPIS30SSF250HYD, SDL), a muffle furnace (DMF-12), and a scanning electron microscope (SEM) (EVO 08).
Preparation of JSC
Jute sticks were obtained from Gaibandha District, Bangladesh, then cut into 3- to 4-in. small pieces, and washed by hand with distilled water. The washed material was then dried at 80 °C for 1 day in an oven before being cooled at room temperature. Afterwards, the material was carbonized at 350 °C in a muffle furnace for 3.5 h, followed by grinding using a mortar and pestle to increase its surface area. Finally, it was sieved through a 100-mesh (150-μm) sieve before being stored in a plastic container for future use.
Preparation of the spike solution of RR dye
For 1,000 mg/l spike solution preparation, accurately weighed 1 g of RR dye was added to enough distilled water to make a total volume of 1,000 ml in a measuring flask. The remaining concentrations were prepared by diluting the prepared spike solution using distilled water as required.
Adsorption study
Equilibrium study
Here, Qe indicates adsorption capacity (mg/g), KL indicates the Langmuir constant (L/mg), Qmax indicates Langmuir adsorption capacity (mg/g), and Ce indicates equilibrium concentration of RR after adsorption (mg/l).
Here, Qe indicates adsorption capacity (mg/g), Kf indicates Freundlich constant, n indicates adsorption intensity, and Ce indicates equilibrium concentration of RR after adsorption (mg/l).
Kinetic modelling
Here, Qe indicates concentration of RR at equilibrium time (mg/g), K1 indicates PFO rate constant (min−1), Qt indicates concentration at time t (mg/g), K2 indicates PSO rate constant (g mg−1 min−1).
Pre-treatment and dyeing of the fabric sample
Pre-treatment and dyeing recipe of the fabric sample
Pre-treatment recipe . | Dyeing recipe . | ||||
---|---|---|---|---|---|
Chemicals . | Concentration . | Remarks . | Dyes/Chemicals . | Concentration . | Remarks . |
Wetting agent (Lissapol N) | 1.5 ml/l | 98 °C × 1 h | Wetting agent (Lissapol N) | 1.5 ml/l | 60 °C × 70 min |
Sequestering agent (EDTA) | 1 g/l | Sequestering agent (EDTA) | 1 g/l | ||
Scouring agent (NaOH) | 2 g/l | Salt (NaCl) | 40 g/l | ||
Bleaching agent (H2O2) | 2 g/l | Fixing agent (Soda ash) | 6 g/l | ||
Detergent | 2 ml/l | Dye (RR) | 1%* | ||
Stabilizer (Na2SiO3) | 1.5 g/l | Neutralizer (CH3COOH) | 1 g/l | 55 °C × 10 min | |
Neutralizer (CH3COOH) | 1.2 g/l | 55 °C × 10 min | Soaping agent | 1 g/l | 80 °C × 10 min |
Peroxide killer | 0.25 ml/l | 55 °C × 10 min | * = on the weight of material. |
Pre-treatment recipe . | Dyeing recipe . | ||||
---|---|---|---|---|---|
Chemicals . | Concentration . | Remarks . | Dyes/Chemicals . | Concentration . | Remarks . |
Wetting agent (Lissapol N) | 1.5 ml/l | 98 °C × 1 h | Wetting agent (Lissapol N) | 1.5 ml/l | 60 °C × 70 min |
Sequestering agent (EDTA) | 1 g/l | Sequestering agent (EDTA) | 1 g/l | ||
Scouring agent (NaOH) | 2 g/l | Salt (NaCl) | 40 g/l | ||
Bleaching agent (H2O2) | 2 g/l | Fixing agent (Soda ash) | 6 g/l | ||
Detergent | 2 ml/l | Dye (RR) | 1%* | ||
Stabilizer (Na2SiO3) | 1.5 g/l | Neutralizer (CH3COOH) | 1 g/l | 55 °C × 10 min | |
Neutralizer (CH3COOH) | 1.2 g/l | 55 °C × 10 min | Soaping agent | 1 g/l | 80 °C × 10 min |
Peroxide killer | 0.25 ml/l | 55 °C × 10 min | * = on the weight of material. |
(a) Pre-treatment and (b) dyeing process curve of the fabric sample.
It is to be noted that a wetting agent, i.e., Lissapol N, helps in wetting the fabric by reducing the surface tension of water, while detergents are used to remove dirt from fabric. A sequestering agent, i.e., ethylenediamine tetraacetic acid (EDTA), is used as a chelating agent to prevent the metal ions present in hard water from interfering with the pre-treatment process and dyeing chemicals. Furthermore, a scouring agent, i.e., NaOH, is used for removing the oil, wax, and pectin of cotton fibres. Their (non-cellulosic portion) removal is crucial to making the fabric hydrophilic, which plays an important role in the dyeing process for even dyeing (Mojsov 2018). To decolourize the natural colour of the fabric and achieve a white appearance, a bleaching agent, i.e., H2O2, is used. This bleaching step provides the perfect shade to the fabric, and during this bleaching process, perhydroxyl ions () are produced from H2O2 that got stabilized with the help of a stabilizer (Na2SiO3). Some peroxide killers are used after the completion of the bleaching process for deactivating H2O2 that otherwise may cause problems in subsequent processes. Furthermore, a fixing agent, namely, soda ash, is used for ionizing the cotton fabric so that it can react with RR dye via covalent bond formation. For reducing the repulsive forces between partially negative cotton fabric in water and anionic RR dye, salt (NaCl) is used. Since pre-treatment and dyeing processes are carried out in an alkaline medium, , a neutralizer, such as CH3COOH, is used for neutralizing the fabric. A soaping agent is used to remove the unfixed dye from the fabric surface.
Collection of the effluent from the fabric sample dyeing bath
The effluent from the dye bath (all the liquor from pre-treatment, dyeing, and post-treatment processes) was collected for a real implication of the JSC adsorbent under optimized conditions to determine the efficiency of removing RR dye from the dye bath effluent, which contains various auxiliaries along with the dye solution.
Collection of the actual textile dye effluent
The raw textile dye effluent was collected from a textile industry in Narayanganj, Bangladesh. The obtained raw effluent was light purple and emitted an unpleasant odour, as it is a mixture of different dyes, including disperse and reactive dyes (dichlorotriazine-based dyes including RR), and some other agents, like a wetting agent, a sequestering agent, a scouring agent, a bleaching agent, a detergent, a stabilizer, a neutralizer, a peroxide killer, etc., in variable amounts. The samples obtained were stored in plastic bottles in the absence of light at room temperature to avoid interaction with sunlight (that will otherwise initiate dye degradation) (Venkataraghavan et al. 2020). The pH of the sample obtained was observed to be 8, which was then adjusted to pH 1 with the help of a 1 M H2SO4 solution. A UV–vis spectrophotometer was used for optimization of the maximum wavelength (λmax), which was observed to be 402 nm. The sample was then diluted to obtain a concentration of 30 mg/l with the help of a calibration curve. Afterwards, an adsorption experiment was conducted with a real textile raw sample under optimized conditions. The removal percentage and adsorption capacity (mg/g) of the sample were calculated with the help of Equations (1) and (2), respectively.
RESULTS AND DISCUSSION
FTIR, SEM, and SEM–EDX analyses of JSC
SEM results of (a) virgin JSC and (b) JSC after RR dye adsorption. EDX spectra of (c) virgin JSC and (d) JSC after RR dye adsorption.
SEM results of (a) virgin JSC and (b) JSC after RR dye adsorption. EDX spectra of (c) virgin JSC and (d) JSC after RR dye adsorption.
Furthermore, the pre-adsorption SEM–EDX analysis (Figure 3(c)) shows that JSC contains a large amount of carbon (C, 71.74%) and oxygen (O, 28.26%), which are available in cellulose, hemicellulose, and lignin. However, after dye adsorption, as shown in Figure 3(d), the inclusion of new atoms like nitrogen (N), sodium (Na), sulphur (S), and chlorine (Cl), represents the adsorption of –N = N–, –SO3Na, etc. groups of RR dye onto JSC.
Effect of pH and adsorbent dose
Removal percentage of RR dye for (a) variable pH levels (where pH = 1–11, initial concentration of RR = 10 mg/l, JSC dose = 0.2 g, contact time = 20 min, and temperature = 30 ± 2 °C). (b) Removal percentage of RR dye for (a) variable adsorbent doses (where pH = 1),initial concentration of RR = 20 mg/l, JSC dose = 0.1–1.0 g, contact time =20 min, and temperature = 30 ± 2 °C).
Removal percentage of RR dye for (a) variable pH levels (where pH = 1–11, initial concentration of RR = 10 mg/l, JSC dose = 0.2 g, contact time = 20 min, and temperature = 30 ± 2 °C). (b) Removal percentage of RR dye for (a) variable adsorbent doses (where pH = 1),initial concentration of RR = 20 mg/l, JSC dose = 0.1–1.0 g, contact time =20 min, and temperature = 30 ± 2 °C).
For optimization of the adsorbent dose, experiments were performed by preparing RR dye solutions having a concentration of 20 mg/l at an optimized pH value, i.e., pH 1. Variable JSC doses from 0.1 to 1 g were added to the solution, followed by continuous shaking at 120 rpm speed. The contact time and reaction temperature were set to be 20 min at 30 ± 2 °C, respectively, followed by calculating the removal percentage using Equation (1) according to the methodology followed by Batool et al. (2021) . The results are shown in Figure 4(b), which illustrates that the dye removal percentage displayed a notable upsurge up to 0.6 g of adsorbent owing to the availability of free adsorption sites on the surface of the adsorbent. However, after 0.6 g, any further increase in adsorbent dose results in no significant change. This trend aligns with previous research (Aziz et al. 2018), which observed a similar phenomenon in removing anionic dyes. The reason may be the saturation of available adsorption sites by dye molecule, resulting in no significant rise in removal percentage at a fixed dye concentration.
Effect of time and RR concentration
Removal percentage of RR dye for (a) variable time durations (where pH = 1, initial concentration of RR = 100 mg/l, JSC dose = 0.6 g, contact time = 5–120 min, and temperature = 30 ± 2 °C). Removal percentage of RR dye for (b) variable concentrations (where pH = 1, initial concentration of RR = 10–100 mg/l, JSC dose = 0.6 g, contact time = 20 min, and temperature = 30 ± 2 °C).
Removal percentage of RR dye for (a) variable time durations (where pH = 1, initial concentration of RR = 100 mg/l, JSC dose = 0.6 g, contact time = 5–120 min, and temperature = 30 ± 2 °C). Removal percentage of RR dye for (b) variable concentrations (where pH = 1, initial concentration of RR = 10–100 mg/l, JSC dose = 0.6 g, contact time = 20 min, and temperature = 30 ± 2 °C).
Another important parameter affecting the adsorption process is dye concentration, and for its optimization, experiments were performed by preparing RR dye solutions having variable concentrations ranging from 10 to 100 mg/l with an optimized solution pH value of 1. The optimal JSC dose of 0.6 g was added to the solution and shaken well at 120 rpm speed for 20 min at 30 ± 2 °C, followed by calculating the removal percentage using Equation (1). The results (Figure 5(b)) depict a decreasing trend in dye removal percentage with increasing the initial dye concentration. The data indicated that at a concentration of 10 mg/l, dye removal efficiency was the maximum, i.e., 93.12%, which gradually decreased to 64.68% with an increase in concentration to 100 mg/l. Based on these results, a dye concentration of 10 mg/l was selected as an optimum dye dosage. This inverse relationship between the initial dye concentration and removal efficiency may be attributed to the saturation of active adsorption sites on the adsorbent, leading to their low availability for dye adsorption. Furthermore, this effect is compounded by the repulsions between dye molecules, which also retards the adsorption process at higher dye concentrations. Similar trends have been reported earlier in the literature (Zaman et al. 2021).
Isotherm modelling
Various isotherm parameters of RR adsorption on JSC
Isotherm . | Isotherm parameter . | |||
---|---|---|---|---|
Langmuir | Qmax (mg/g) | KL (dm3/mol) | RL | R2 |
3.08 | 0.1765 | 0.06–0.4 | 0.989 | |
Freundlich | Kf(mg/g) | 1/n | R2 | |
5.16 × 102 | 0.4959 | 0.949 |
Isotherm . | Isotherm parameter . | |||
---|---|---|---|---|
Langmuir | Qmax (mg/g) | KL (dm3/mol) | RL | R2 |
3.08 | 0.1765 | 0.06–0.4 | 0.989 | |
Freundlich | Kf(mg/g) | 1/n | R2 | |
5.16 × 102 | 0.4959 | 0.949 |
Adsorption isotherm graphs of RR onto JSC: (a) Langmuir isotherm and (b) Freundlich isotherm.
Adsorption isotherm graphs of RR onto JSC: (a) Langmuir isotherm and (b) Freundlich isotherm.
The comparison of some studies on RR dye adsorption (Table 3) indicates that different types of adsorbents possess different adsorption capacities under variable experimental conditions. This comparative analysis demonstrates the superior performance of JSC against various adsorbents, underscoring its potential as a sustainable solution for RR dye removal, aligning with the concept of green chemistry.
Comparison of some adsorption studies on RR dye removal
Adsorbent . | Adsorption capacity (mg/g) . | pH . | Ref . |
---|---|---|---|
Commercial charcoal | 0.074 | 7 | Ara et al. (2013) |
Wood residues (Bagassa guianensis Aubl) | 0.71 | 2 | Monteiro et al. (2017) |
Jute stick charcoal | 3.08 | 1 | Present work |
Coconut mesocarp | 3.97 | 2 | Monteiro et al. (2017) |
Sawdust activated carbon | 8 | 7 | Ara et al. (2013) |
MnO2 nanoparticles with cetyltrimethylammonium bromide | 40 | 1 | Mahmoud et al. (2022) |
Chitosan | 155.72 | 5.4 | Kabir et al. (2014) |
Chlorella vulgaris | 196 | 2 | Aksu & Tezer (2005) |
Adsorbent . | Adsorption capacity (mg/g) . | pH . | Ref . |
---|---|---|---|
Commercial charcoal | 0.074 | 7 | Ara et al. (2013) |
Wood residues (Bagassa guianensis Aubl) | 0.71 | 2 | Monteiro et al. (2017) |
Jute stick charcoal | 3.08 | 1 | Present work |
Coconut mesocarp | 3.97 | 2 | Monteiro et al. (2017) |
Sawdust activated carbon | 8 | 7 | Ara et al. (2013) |
MnO2 nanoparticles with cetyltrimethylammonium bromide | 40 | 1 | Mahmoud et al. (2022) |
Chitosan | 155.72 | 5.4 | Kabir et al. (2014) |
Chlorella vulgaris | 196 | 2 | Aksu & Tezer (2005) |
Kinetic modelling
Kinetic model parameters of RR adsorption on JSC
Kinetic model . | Parameters . | |||
---|---|---|---|---|
Pseudo-first-order model | Qe, exp (mg/g) | Qe, cal (mg/g) | K1 (min−1) | R2 |
2.849 | 8.44 | −0.00101 | 0.414 | |
Pseudo-second-order model | Qe, exp (mg/g) | Qe, cal (mg/g) | K2 (g mg−1 min−1) | R2 |
2.849 | 2.862 | 0.175 | 0.999 |
Kinetic model . | Parameters . | |||
---|---|---|---|---|
Pseudo-first-order model | Qe, exp (mg/g) | Qe, cal (mg/g) | K1 (min−1) | R2 |
2.849 | 8.44 | −0.00101 | 0.414 | |
Pseudo-second-order model | Qe, exp (mg/g) | Qe, cal (mg/g) | K2 (g mg−1 min−1) | R2 |
2.849 | 2.862 | 0.175 | 0.999 |
Kinetics model plot of RR onto JSC: (a) pseudo-first-order model and (b) pseudo-second-order model.
Kinetics model plot of RR onto JSC: (a) pseudo-first-order model and (b) pseudo-second-order model.
Removal percentage analysis of the effluent from the fabric sample dye bath
The effluent was collected from the sample dye bath, and by lowering the pH to 1, 25 ml of the solution was separated for absorbance measurements. Subsequently, the absorbance was measured by using a UV–visible spectrophotometer, where a dye concentration of the effluent was obtained as 25.3 mg/l based on the calibration curve. After that, the optimized conditions of pH = 1, adsorbent dosage = 0.6 g, adsorption time = 20 min, and solution temperature = 30 ±2 °C were inputted to the system. The results of the study show that the colour removal percentage was 62.4% for the dye bath effluent, whereas the removal percentage for 30 mg/l was 89.12%. Here, the removal percentage was reduced because of the presence of different types of chemicals like the detergent, wetting agent, sequestering agent, bleaching agent, stabilizer, NaOH, CH3COOH, NaCl, etc.
Application of the developed procedure for treating the actual textile effluent
To evaluate the scaled application of JSC to a wastewater stream with a matrix of constituents (Kanamarlapudi et al. 2016), efforts have been devoted to the use of JSC for treating actual textile wastewater (instead of using an aqueous RR dye solution). An experiment was performed under optimum batch conditions that include a solution pH of 1 using an adsorbent dosage of 0.6 g for an optimum adsorption time of 20 min. The concentration of the raw sample was 30 mg/l (obtained from the standard curve). The results of the study reveal that nearly 52.6% of adsorption takes place for 30 mg/l. This removal percentage was less than that obtained with adsorption of the model RR solution prepared at the lab scale (where removal percentage was 89.12% for 30 mg/l) and dyed sample fabric bath (62.4% removal for 25.3 mg/l). This declination of the removal percentage of the textile raw sample by JSC is attributed mainly to the presence of other interfering ions in textile wastewater, such as different anions (phosphate, chloride, carbonates, etc.) and cations (sodium, potassium, calcium, etc.) (Ay et al. 2012), pre-treatment chemicals (already discussed in Table 1), and some other dyes. The results of the study conform to the fact that the studied procedure could be practical to actual industrial wastewater containing different interfering substances (Javaid et al. 2011). However, implementation of the developed procedure at a larger industrial scale involving a mixture of different effluents coming from various industrial spots needs to be expanded by considering the cost and potential risks of implementation. Many fascinating studies on treating actual wastewater for investigating the scaled application of the developed method are available in the literature (Vinodhini & Das 2010; Singh et al. 2012; Ullah et al. 2013).
CONCLUSION
The application of adsorption techniques for removing toxic dyes from water, especially in resource-constrained developing countries, is gaining significance. Jute stick, an easily available and cost-effective adsorbent, gained importance as a promising adsorbent to remove dyes. Herein, the study includes the adsorptive removal of RR from the textile dyeing effluent by JSC. The FTIR study revealed the presence of some functional groups, including –C–O, –COOH, –OH, etc., which are responsible for developing chemical interactions with the dye. The surface of JSC was examined using SEM analysis, which shows a porous nature, rough texture, and abundance of active sites on JSC capable of adsorbing the RR dye. The post-adsorption EDX report shows the inclusion of new atoms like nitrogen (N), sodium (Na), sulphur (S), and chlorine (Cl), which represent the adsorption of –N = N–, –SO3Na, etc. groups of RR on JSC. The highest adsorption efficiency observed was 93.12% at a lower pH level. Two adsorption isotherms and two kinetic models were studied and investigated, and the obtained experimental data exhibited compatibility with the PSO and Langmuir models. These results conform to chemical interaction and monolayer adsorption of RR on the JSC adsorbent. The implication of the developed study was carried out on the effluent from the fabric sample dyed with RR in a bath and the actual raw textile effluent containing various agents like the wetting agent (for wetting fabric), EDTA (chelating agent), NaOH (for removing oil, wax, pectins of cotton fibres), NaCl (for decreasing the repulsion of partially negative cotton fabric and anionic RR dye in water), CH3COOH (for neutralizing the fabric), soaping agent (for removing the unfixed dye from the fabric surface), etc. The maximum dye removal of 62.4 and 52.6% was obtained. The findings suggest that JSC is a promising adsorbent for the removal of RR dye in the textile dyeing and printing sector.
ACKNOWLEDGEMENTS
The authors are grateful to the University of Chittagong, Noakhali Science and Technology University for their generous support and for providing characterization facilities throughout the research work.
FUNDING
This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
DATA AVAILABILITY STATEMENT
All relevant data are included in the paper or its Supplementary Information.
CONFLICT OF INTEREST
The authors declare there is no conflict.