Value-added utilization of maize cobs waste as an environmental friendly solution for the innovative treatment of carbofuran

A new route for the conversion of maize cobs waste, a natural low-cost lignocellulosic biomass abundantly available from the food processing industries into an eco-friendly bio-sorbent (CC) via chemical treatment has been presented. The effectiveness for the adsorptive removal of a highly hazardous carbamate derivative pesticide, carbofuran from the aqueous solution was attempted. The operational parameters including the effects of modification agents and chemical impregnation ratio on the adsorption capability were investigated. The porosity, functionality and surface chemistry of CC were featured by means of low temperature nitrogen adsorption, elemental analysis, scanning electron microscopy, Fourier transform infrared spectroscopy, evaluation of surface acidity/basicity and zeta potential measurement. The effects of adsorbent dosage, initial concentration, contact time and solution pH on the adsorption performance were evaluated in a batch mode study. Equilibrium data were simulated by non-linear fittings using the Freundlich, Langmuir, and Temkin isotherm models. Kinetic modeling was fitted to the pseudo-first-order and pseudo-second order equations. Langmuir isotherm model provided a better correlation to the experimental data, with a maximum monolayer adsorption capacity of 149.15 mg/g, while the adsorption kinetic was best fitted to the pseudo-second-order kinetic model. The results illustrated the potential of maize cobs waste derived biosorbent for the on-site remediation of pesticide contaminated wastewater. (C) 2016 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.