Sustainable valorization of chicken bone waste into high-performance activated carbon for efficient removal of organophosphorus pesticides

Abstract

This study reports the sustainable valorization of chicken bone waste into high-performance activated carbon (CBAC) for the removal of malathion, an organophosphorus pesticide, from aqueous systems. CBAC was synthesized via KOH activation at 800 °C, yielding a microporous material with a BET surface area of 1,154 m²/g and total pore volume of 0.89 cm³/g. FTIR, SEM, and BET analyses confirmed the presence of abundant oxygen-containing functional groups and a highly developed pore structure. Adsorption experiments revealed a maximum capacity of 84.03 mg/g for malathion at an initial concentration of 40 mg/L, with an optimal pH of 6.0 achieving 96.4% removal efficiency. Batch adsorption studies revealed optimal performance at pH 6, with an equilibrium adsorption capacity of 142.8 mg/g, fitting well to the Langmuir isotherm (R² = 0.992) and pseudo-second-order kinetics (R² = 0.987). The intra-particle diffusion model indicated a multi-stage adsorption mechanism involving surface interaction and pore diffusion. Comparative tests demonstrated CBAC’s superior efficiency over commercial activated carbon. The adsorption process was thermodynamically spontaneous and endothermic. A preliminary cost estimation suggested that CBAC production from waste chicken bones is economically feasible, supporting its potential for large-scale application. This work demonstrates a circular bioeconomy approach to waste valorization while offering an effective and low-cost adsorbent for pesticide remediation.