Comparison of color removal from reactive dye contaminated water by systems containing fungal biosorbent, active carbon and their mixture

The adsorption of Everzol Black (EB) from synthetic aqueous solution onto active carbon (AC) and dried fungal biosorbent (Rhizopus arrhizus) was studied under the same experimental conditions. The effects of initial dye concentration, adsorbent dosage and contact time were examined at a batch-scale level. As an alternative to AC, fungus was investigated as a low-cost adsorbent for dye removal. The amount of EB adsorbed onto AC was lower compared with fungal biosorbent; dye adsorption capacity of AC and fungal biosorbent were 94.48 and 106.61 mg/g, respectively. The adsorbent dosage experiments showed that 4 g/L biosorbent removed 100% of EB (C_o: 114.39 mg/L) after 2 hours. The results obtained from this study showed that biosorbent effectively removed reactive dye from dye-containing water in a short time period. Langmuir and Freundlich adsorption isotherm models were used for mathematical description of the biosorption equilibrium data; the Freundlich model was found to exhibit good fits to the experimental data. According to the Freundlich isotherm, the maximum dye adsorption capacities of AC and biosorbent were calculated as 344.82 and 357.14 mg/g, respectively. The Fourier transform infrared spectroscopy spectral analysis showed the involvement of functional groups for dye bindings.