Antibiotics removal from water by adsorption activated carbon of bacterial cellulose source

The overuse of antibiotics in developing countries has exacerbated antibiotic resistance, particularly due to contamination of water systems. This study addresses this challenge by synthesizing activated carbon derived from bacterial cellulose (AC-BC) for efficient adsorption of amoxicillin (AMOX) and cephalexin (CEX) from aqueous solutions. Bacterial cellulose (BC), produced sustainably by Komagataeibacter using waste coconut water, served as the precursor for AC-BC. The synthesized AC-BC exhibited a yield of 19.46±3.92% (dry weight basis) and met ASTM standards in proximate analysis, excluding ash content. Structural characterization revealed a hierarchical pore structure, supported by an iodine number of 1360.59 mg g-1 and methylene blue adsorption of 24.01%, with SEM imaging confirming diverse pore sizes. BET analysis demonstrated a high specific surface area (204.68 m² g-1), total pore volume (0.1475 cm³ g-1), and average pore diameter (2.8825 nm). Functional groups (hydroxyl, carboxyl, ether) and a semi-crystalline structure were identified via FTIR and XRD, respectively. Optimal batch adsorption conditions (60 mg L-1 initial concentration, 60-min contact time, 0.2 g adsorbent dosage, pH 7, 30°C) achieved maximum capacities of 4.578 mg g-1 (AMOX) and 4.288 mg g-1 (CEX). Adsorption isotherms aligned with the Langmuir model, indicating monolayer adsorption, while kinetics followed a pseudo-second-order model. Thermodynamic analysis revealed a spontaneous (ΔG° < 0), exothermic (ΔH° < 0), and entropy-driven (ΔS° > 0) process. These findings highlight AC-BC as a promising, low-cost adsorbent for antibiotic removal. The use of renewable BC from agro-industrial waste underscores its environmental and economic viability, offering a sustainable strategy to mitigate water contamination and combat antibiotic resistance. GRAPHICAL ABSTRACT HIGHLIGHTS Activated carbon of bacterial cellulose sources (AC-BC) has been used as highly effective adsorbent for amoxicillin (AMOX) and cephalexin (CEX) Bacterial cellulose source is a natural, renewable, environmentally friendly and low-cost.