Optimized synthesis of activated carbon from date palm seeds for efficient crude oil adsorption in wastewater treatment
Salem S. Bamerdhah, Nadavala Siva Kumar, Ebrahim H. Al‐Ghurabi, Mourad Boumaza, Mohammad Asif
Abstract
The effective treatment of oil-contaminated wastewater is a critical environmental challenge. This study demonstrates a robust pathway for synthesizing high-performance activated carbon (AC) from date palm seed waste for the removal of crude oil. A two-step process involving pyrolysis and subsequent KOH chemical activation was systematically optimized by varying key parameters, including temperature, time, and impregnation ratio. The optimized adsorbent, AC5 (prepared at a 4:1 KOH: biochar ratio, 700 °C, for 2 h), exhibited a high surface area of 2151 m²/g and an exceptional crude oil adsorption capacity of 1816 mg/g. A key finding is that maximum surface area alone does not dictate performance for complex adsorbates; AC5 significantly outperformed a sample with a higher surface area (2417 m²/g), a result attributed to its more favorable surface chemistry as confirmed by FTIR analysis. The adsorption process was best described by the Freundlich isotherm and pseudo-second-order kinetic models. Crucially, the performance of the optimized AC represents an improvement of nearly an order of magnitude over previously reported date-seed carbons for oil removal and surpasses that of many other biomass-derived adsorbents. This work establishes a clear synthesis pathway for valorizing an abundant agricultural waste into a superior adsorbent for oil spill remediation.