ENHANCING THE ADSORPTION CAPACITY OF Pb2+ AND Cu2+ IONS IN AQUEOUS SOLUTION USING POTASSIUM PERMANGANATE-MODIFIED BIOCHAR

Abstract

This study aims to enhance the adsorption capacity of sawdust-derived biochar (BC-MC) for heavy metal ions by modifying it with a KMnO₄ solution. The adsorption performance of KMnO₄-modified biochar (BC-KMnO₄) was evaluated by examining the impact of various single-variable factors: pH (2.0 – 6.0), initial concentration of the metal ions (25 – 200 mg‧L⁻¹), adsorption time (5 – 1440 minutes), and adsorbent mass (0.05 – 0.10 g). The findings indicate that the adsorption of Cu²⁺ and Pb²⁺ ions onto BC-KMnO₄ followed the pseudo-second-order kinetic model and the monolayer adsorption mechanism, suggesting that the Langmuir adsorption isotherm model best describes the adsorption process. The BC-KMnO₄ exhibited a maximum adsorption capacity of 24.15 mg‧g⁻¹ for Cu²⁺ and 90.09 mg‧g⁻¹ for Pb²⁺. Overall, the study confirms that KMnO₄ modification significantly enhances the adsorption capacity of BC-MC for metal ions, making it a promising low-cost and environmentally friendly material for water treatment applications.