Low-cost sorbent for removing glyphosate from aqueous solutions for non-potable reuse

Abstract

This study aimed to determine the removal of glyphosate from aqueous solutions by adsorption with pulverized activated carbon, considering the possibility of including this method as an effluent treatment to be adopted for non-potable reuse. Pareto analysis techniques and response surface analysis were used to evaluate the efficiency and conditions of the process and its effects. The adsorbent used was Biocarbon PVU Tobasa, pulverized activated carbon, manufactured by Tobasa Bioindustrial de Babaçu S.A, from the endocarp of the babassu coconut (Attalea ssp) through a process of physical activation with water vapor. The adsorption tests were carried out keeping the initial concentration of the pesticide at 79.5 mg/L. The results show the effects of the correlated variables, obtaining the optimization of the experimental data, reaching the removal efficiency of approximately 60% of the glyphosate, for an adsorbent dosage of 3.2 g, pH 4.6 and speed of agitation 170 rpm. It is verified that activated carbon can be used as an adsorbent in the removal of glyphosate, even at high concentrations, proving to be an alternative treatment for wastewater, capable of obtaining water for non-potable reuse, regarding the presence of glyphosate.

Keywords: activated carbono, adsorption of glyphosate, wastewater reuse.