Development of Adsorbent from Solid Waste of Potato Peel for Decontamination of Wastewater Containing 4-Nitrophenol

Abstract

Discarded potato peels were charred at 5000C and utilized as adsorbents for the reclamation of wastewater contaminated with 4-nitrophenol. Batch studies investigating the effects of several parameters like pH, contact time, temperatures were carried out to determine the optimum adsorption condition using synthetic wastewater. Adsorption was found to be more favorable under acidic medium. Column studies, kinetic studies and thermodynamic studies were also performed to understand the applicability and feasibility of the adsorbent for industrial usage. The thermodynamic parameters like ΔG0, ΔH0 and ΔS0 were evaluated by using the van’t Hoff plot. The adsorption process was found to be spontaneous and endothermic in nature as evident from Δ G0and ΔH0 values of -3.985 kJ/mol and 62.512 kJ/mol respectively. Several isotherm models were applied and Freundlich isotherm model with coefficient of determination value (R2 = 0.998) was found as the best fit isotherm model to describe the equilibrium adsorption data. Certain physico-chemical and spectroscopic characterization of potato peels char (PPC) were analyzed in an attempt to better understand the adsorption process.