Treating contaminated water with waste: Removal of hazardous Eriochrome black T dye from water system using poultry feather waste

Eriochrome black T (EBT) dye and poultry feather waste are hazardous substances that pose significant environmental threats if not treated or managed properly. Therefore, the development of effective and environment-friendly management methods is crucial. This study investigated the potential of poultry feathers as sustainable and cost-effective biosorbents for removing EBT from water. Batch biosorption experiments revealed that the optimal conditions for EBT biosorption onto feathers were pH 7, 50 °C, and a feather dosage of 4 g L⁻¹. Under these conditions, the maximum biosorption capacity and removal efficiency were 17.1 μmol g⁻¹ and over 98.5 %, respectively, at EBT concentrations of 150 μmol L⁻¹. The pseudo-second-order kinetics and Langmuir isotherm models provided the best fit for the experimental data, indicating that EBT was chemisorbed onto the feather surface to form a monolayer. Additionally, film and intraparticle diffusion were the primary mechanisms governing biosorption. EBT biosorption was spontaneous and endothermic and was driven by an increase in entropy at elevated temperatures. Experiments conducted using environmental water under ambient conditions validated the efficacy of poultry feathers in significantly reducing both the EBT dye concentration and chemical oxygen demand. Fourier-transform infrared spectroscopy and scanning electron microscopy analyses revealed that the EBT dye was adsorbed onto the feather surface through interactions with its functional groups. This study demonstrates the potential of readily available and low-cost poultry feather waste as an effective and sustainable biosorbent for removing hazardous dyes, such as EBT, from contaminated water, offering a promising solution for both waste management and environmental remediation in low-income countries.