Elimination of Fipronil insecticide by adsorption technique from aqueous solution by Cu-13X zeolite composite: isotherms, kinetic and thermodynamic studies

Abstract

ABSTRACT The present investigation was carried out to evaluate the performance of copper modified zeolite-13X as an adsorbent for the removal of Fipronil (FP) pesticide from synthetic wastewater. The experiments on adsorptive removal were carried out varying different parameters such as pH of the solution (1 pH-10 pH), contact time (20 min – 120 min), stirring speed (50 rpm −200 rpm), a dose of adsorbent (1 g/L to 4 g/L), initial concentration of the solution (500 mg/L to 1000 mg/L). The removal of FP pesticide from its aqueous solution was found to be maximum i.e. 92.3%. At optimum pH 3, 84.2% removal of Fipronil was obtained. The removal of Fipronil decreases with the increase in the initial concentration of pesticides. The effect of temperature on Fipronil removal was also studied. At 25°C, the maximum percent removal is reported to be 92%. Also, the maximum removal is 92.3% at an optimum stirring speed of 200 rpm. The Freundlich isotherm fitted the experimental data well whereas the process of adsorption obeyed second-order kinetic model. The thermodynamics study of adsorption was also carried out. The results of the investigation revealed that copper-doped zeolite could be used as a potential sorbent towards the eradication of Fipronil pesticide from wastewater.