Biosorption of Cu²⁺ from Aqueous Solution using <i>Aspergillus oryzae</i> and Baker's Yeast

Abstract

Present work evaluates the ability of Aspergillus oryzae and commercial dry Baker's yeast to effectively remove Cu2+ ions from aqueous solutions. Batch experiments were carried out in order to analyze sorption behavior of metal-sorbent system at different biosorbent dosage, and initial metal concentration. Various pre-treatment methods were adopted to modify the biomass, and effect of pre-treatment was investigated on biosorption efficiency. Till now, very few efforts are dedicated for application of immobilized biosorbents in literature therefore further investigations were done on the biosorption efficiency of biomass immobilized in a natural matrix which might augment stability, mechanical strength, and reusability of the biomass. Approximately 86 and 95% biosorption of copper was attained under optimum reaction conditions using Loofah immobilized with Baker's yeast, and A. oryzae, respectively. Desorption efficiency of the immobilized biomass was evaluated by performing successive biosorption-desorption cycles. Successful regeneration of Loofah sponge loaded with immobilized biosorbent was illustrated by desorbing more than 95% copper. Characterization studies were performed to examine the changes in surface morphology, and surface chemistry before and after adsorption.