Nano-modified feather keratin derived green and sustainable biosorbents for the remediation of heavy metals from synthetic wastewater.

In this study, we employed a facile method to synthesize feather keratin derived biosorbents using water dispersed graphene oxide. The successful cross-linking of feather keratin with graphene oxide was investigated through X-ray photoelectrons spectroscopy (XPS), scanning and transmission electron microscopy, and Brunauer–Emmett–Teller (BET) analysis. The modifications resulted in increased surface area of the keratin proteins with substantial morphological changes including the development of cracked and rough patches on the surface. The chicken feather keratin/graphene oxide based biosorbents exhibited excellent performance for the simultaneous removal of metal oxyanions including arsenic (As), selenium (Se), chromium (Cr) and cations including nickel (Ni), cobalt (Co), lead (Pb), cadmium (Cd) and zinc (Zn) up to 99%, from polluted synthetic water containing 600 μgL−1 of each metal concentration in 24 h. The insights into the biosorption mechanism revealed that the electrostatic interaction, chelation and complexation primarily contributed to the removal of multiple heavy metal ions in a single treatment. This study has demonstrated that modification of chicken feather keratin with graphene oxide is an effective way to improve its sorption capacity for removing multiple trace metal ions from contaminated water. [Display omitted] • Keratin based biosorbents are renewable, sustainable and environmentally benign. • Nanomodification of keratin led to the improvement of heavy metals bio-adsorption. • Keratin derived biosorbents removed As (III) and Se (VI) up to 99%. • Bio-adsorption of metal ions was carried out via electrostatic interaction, chelation and complexation. • Developed biosorbents have great potential to be used for simultaneous removal of multiple metals from contaminated water. [ABSTRACT FROM AUTHOR]