Comparison of biosorption efficiency for hexavalent chromium remediation in synthetic wastewater using unmodified and chemically modified chicken feathers

Abstract

The aim of the present study was to compare the effectiveness of raw chicken feathers (RCFs), NaOH and ethylenediamine-modified chicken feathers (MCFs), and xanthate-modified chicken feathers (XMCFs), treated with both NaOH, ethylenediamine, and carbon disulfide. The physicochemical characteristics of the biosorbents were analyzed using attenuated total reflection Fourier transform infrared spectrophotometry (ATR-FTIR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), adsorption of N₂ at −196°C and point of zero charge determination (pH_pzc). The biosorption of Cr(VI) using MCFs and XMCFs was evaluated through various parameters, namely, pH, biosorbent amount, and contact time in batch experiments. The results showed a significant increase in the biosorption capacities of MCFs (90.90 mg/g) and XMCFs (100 mg/g) compared to RCFs (52.63 mg/g). The batch adsorption experiments indicated that the optimal conditions for biosorption were pH 2.0, with an equilibrium contact time of 90 min for RCFs, and 60 min for both MCFs and XMCFs. The optimal biosorbent concentrations were 16 g L⁻¹ for RCFs and 12 g L⁻¹ for both MCFs and XMCFs. The biosorption behavior was well described by the Langmuir isotherm and pseudo-second-order kinetic models. The thermodynamic parameters indicated that the biosorption of Cr(VI) onto the biosorbents was a spontaneous and endothermic process. Desorption analysis was carried out using a 0.1 M NaOH solution.

Graphical abstract

Keywords:

• Biosorption
• chemical modification
• chicken feathers
• hexavalent chromium
• regeneration

Acknowledgements

Authors are thankful to SAIF Centre STIC Kochi (Keral) and to lab staff and research scholars at Department of Chemistry, Govt. V.Y.T. PG. Autonomous College, Durg, (C.G.), India for their support. This work was also supported by FCT—Fundação para a Ciência e a Tecnologia, I.P., under the Scientific Employment Stimulus—Institutional Call (CEECINST/00102/2018) and partially supported by the Associate Laboratory for Green Chemistry—LAQV, financed by national funds from FCT/MCTES (UIDB/50006/2020 and UIDP/5006/2020).

Authors’ contribution

Rupa Chakraborty: Conceptualization, Methodology, Data curation, Formal analysis, Investigation, Resources, Software, Writing—original draft, Writing—review & editing. Anupama Asthana: Conceptualization, Supervision. Ajaya Kumar Singh: Funding acquisition, Project administration, Resources, Software, Writing—review & editing. Sushma Yadav: Conceptualization, Visualization. Sónia A.C. Carabineiro: Validation, Visualization, Writing—review & editing.

Disclosure statement

There are no conflicts to declare.