Chicken Feathers Keratin/ Modified Graphene Oxide Based Biosorbent for Water Remediation

Abstract

Water is one of the most precious resources on the earth and is a life source for all the living organisms. Around 75% of industrial wastewater is being discharged into the freshwater streams and 38% of it released untreated. Worldwide, wastewater from oil sands projects is being released into the water bodies and severely polluting the water resources. The tailings pond water contains toxic metals including lead, cadmium, arsenic, nickel, chromium, and selenium. Reverse osmosis, filtration and disinfection are being used to address the water quality issues. However, these have high cost, shorter life and poor adsorption capacity. We developed an eco-friendly biosorbent from chicken feathers with potential to remove heavy metals. Keratin from chicken feathers is an almost infinite source of natural protein ( >92%). Poultry feathers have a few applications, but large quantities are disposed in landfills that create environmental issues. Chicken feathers were washed, ground, and dissolved using reducing agent. Keratin was isolated from the solution using dialysis followed by freeze drying. Finally, biosorbent was obtained by treating powdered keratin with water dispersed modified graphene oxide and polymerized at high temperature. The biosorbents was tested for metals removal from synthetic contaminated water with concentration of 600, 1000 and 2000 ppb. Adsorption studies were performed using ICP-MS and compared with the commercially available adsorbents. Our study revealed that adsorbent can remove As, Se, Pb, Cu, Cd and Cr with adsorption capacity between 80-99% from the polluted water. This excellent adsorption capacity was ascribed to the incorporation of graphene oxide which increased the surface affinity of the keratin to adsorb heavy metals easily. The synthesis of environmentally benign adsorbent from chicken feathers showed potential to be implemented on larger scale. The study will also provide an alternate for chicken feathers utilization instead of simple disposal that causes environmental concerns.