Investigation of Isotherm Models for the Adsorptive Removal of Amoxicillin from Simulated Solution Using Groundnut Shell Biochar

Student: KINGSLEY CHUKWUNENYE OBIOMA (Project, 2025)
Department of Industrial Chemistry
Ekiti State University, Ado-Ekiti, Ekiti State


Abstract

The persistence of pharmaceutical pollutants, particularly antibiotics like amoxicillin, in water sources poses significant environmental and public health challenges. This study investigates the effectiveness of groundnut shell biochar (GNSB) as an adsorbent for removing amoxicillin from aqueous solutions. GNSB was prepared via pyrolysis and characterized for its adsorption capacity under varying pH, contact times, and initial concentrations. Batch adsorption experiments demonstrated high removal efficiency, with an optimal pH of 6 and a maximum removal efficiency of 88% at lower concentrations. Adsorption data aligned closely with the Langmuir isotherm model, indicating monolayer adsorption on a homogeneous surface, with a maximum capacity of 24.12 mg/g. Freundlich and Temkin isotherms further highlighted the heterogeneous surface properties and adsorbate interactions. This study underscores GNSB's potential as an affordable and sustainable alternative for treating pharmaceutical-contaminated water, advancing environmental remediation efforts.

Keywords
adsorption removal amoxicillin isotherm groundnut shell biochar water environmental capacity