Evaluation of the Removal Efficiency of Lead Ion from Aqueous Solution Using Unmodified and Modified Mahogany Sawdust

Abstract

This study was carried out to evaluate the efficiency of unmodified and modified acid and alkaline mahogany sawdust as adsorbents for the removal of lead (Pb) from aqueous solutions. The modification was done using HCl and NaOH solutions. The batch adsorption method was used to evaluate the performance of each adsorbent under varying conditions, including initial Pb2+ concentration, adsorbent dosage, contact time, and pH. The results showed that the maximum adsorption capacity for the control, acid, and alkaline modified adsorbents were 24.272 mg/g, 21.322 mg/ a n d 14.662 mg/g respectively. Removal efficiency of 98.44% was achieved with the acid-modified sawdust at an initial Pb concentration of 100 mg/L and pH 4 while the maximum removal efficiency by the alkaline and unmodified absorbents were 97.22% and 94.35% respectively. The data analyzed for adsorption kinetics and equilibrium isotherm fitted well with the pseudo-second order kinetic model and the Freundlich isotherm model. This study demonstrated that modified mahogany sawdust is an efficient, eco-friendly adsorbent for treating lead-contaminated water. The findings provide valuable insights for the optimization of mahogany sawdust for practical heavy metal ions removal.