Extraction of Bio Polymers from Crustacean Shells and its Application in Refinery Wastewater Treatment

The fisheries sector is one of the most ancient and important sectors in the world and plays a significant role in providing the nutrition and socio-economic development of the country. The fish processing industry produces huge quantities of wastewater, encompassing significant amounts of contaminants in the form of soluble, colloidal, and particulate matters. The disposal of shellfish waste is a serious issue, and the effluents discharged from seafood-processing plants contain high amounts of Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), dissolved solids, suspended solids, and turbidity. The existing waste management system lacks a cost-effective and environmentally friendly method. The current research focus on the extraction of a biopolymer chitosan from crab shells by ecofriendly methods and its application in refinery wastewater treatment. The chemical structure and crystallinity of the extracted chitosan was confirmed by Fourier Transform Infrared Spectroscopy (FTIR) and X-Ray Diffraction (XRD) analyses. Surface morphology and elemental composition were determined using Scanning Electron Microscopy (SEM), and Energy-Dispersive X-Ray Analysis (EDX). Thermal properties were detected using Thermo Gravimetric Analysis (TGA). The extracted chitosan was successfully employed in the batch treatment of refinery effluent by varying the experimental parameters (refinery effluent solution pH, contact time, dosage of chitosan, and stirring speed) and the optimizations of the processing conditions were established.