LAUSR

Abstract This study evaluates the adsorption efficiency of Cd2+ and Cu2+ by peanut shell biochar (BPS) in monocomponent and bicomponent systems. The characterization indicated that BPS was mesoporous and amorphous, with presence of hydroxyl and carboxylic functional groups, with a pHPZC of 7.9. The effects of pH, stirring speed and adsorbent dosage were investigated, and the best results were obtained at pH 5.9, 200 rpm and 2 g·L−1. In monocomponent systems, the Elovich and BET models had the best adjustment, obtaining maximum adsorption capacity of 0.39 mmol·g−1 for Cd2+ and 0.48 mmol·g−1 for Cu2+, and the adsorption process was spontaneous and endothermic. With regard to bicomponent systems, a model was developed in order to predict the evolution and equilibrium of kinetics. BPS had regeneration potential after desorption. These results demonstrate the viability of the use of BPS for the adsorption of Cd2+ and Cu2+ in both systems.