Fixed bed biosorption and ionic exchange of aluminum by brown algae residual biomass

Abstract

This study aimed to evaluate the ion exchange and biosorption of Al3+ using as biosorbent material residual biomass generated in the alginate extraction process from the brown algae S. filipendula (named RES). The batch mode results showed that ion exchange, mainly with Na+ ions, has important participation in the removal of Al3+ ions by RES. Characterization analyses and blocking assays indicated that carboxylic, amino and sulfonate functional groups play a key role on the Al3+ biosorption. The dynamic system in a fixed packed bed column and the reuse/regeneration of the biosorbent was assessed by breakthrough method. Fixed bed experiments pointed that higher Al3+ removal was achieved at 0.5 mL/min and 1 mmol/L. DualSD model showed superior prediction of experimental data. Biosorption/Desorption cycles demonstrated the reuse feasibility of the biosorbent, which maintained a considerable adsorption capacity in all cycles performed.