Biosorption of Cd(II) by Pleurotus mutilus biomass in fixed-bed column: experimental and breakthrough curves analysis

Abstract

The removal of Cd(II) from aqueous solutions by a Pleurotus mutilus macrofungal biomass was investigated in a fixed-bed column. The experiments were conducted to study the effects of important design parameters such as bed depth (10–15 cm), flow rate (5–20 mL/min), and inlet concentration (30–50 mg/L). The optimum conditions were achieved at 15 cm, 10 mL/min, and 50 mg/L, respectively. The BDST, Thomas, and Adams–Bohart models were also applied to the experimental data to predict the breakthrough curves at various operating parameters. The BDST model was in good agreement with the experimental data. The breakthrough curves were well fitted with the Thomas model (R2 > 0.97), while the Adams–Bohart model was applicable for the initial part of biosorption. The column was regenerated by eluting Cd(II) using 0.05M HNO3 and the biosorbent was reused for three biosorption regeneration cycles. The results show a good regeneration efficiency and a high removal for Cd(II) with a slight decrease in biosorption capacity with cycles. P. mutilus macrofungal biomass was proved to be a potential biosorbent for the removal of Cd(II) in the fixed-bed column.