Advancing Heavy Metal Removal from Industrial Wastewater Using Oil Palm Waste–Based Adsorbent: toward Efficient Adsorption and Commercialization

Abstract Purpose of Review The palm oil industry, as the largest producer of edible oil in the world, generates considerable volumes of biomass waste, including oil palm fronds, trunks, empty fruit bunches, mesocarp fibers, palm kernel shells, and palm oil fuel ash. Improper disposal of these residues contributes to environmental pollution and resource management challenges. This review aims to critically evaluate recent developments in transforming oil palm biomass waste (OPW) into low-cost, high-performance adsorbents for the removal of heavy metals from industrial wastewater, while aligning with zero-waste and circular economy goals. Recent Findings Recent studies have demonstrated that OPW-derived adsorbents, when subjected to particle size reduction and surface functionalization, exhibit significantly enhanced adsorption capacity and recovery efficiency. Notably, activated carbon nanoparticles derived from empty fruit bunch via KOH activation have demonstrated adsorption capacities exceeding 1000 mg/g for Cu 2+ and Pb 2+ , attributed to their ultrafine size and high surface reactivity. These materials also show strong reusability, with over 80% adsorption efficiency retained after multiple regeneration cycles. Integration of OPW adsorbents into dynamic systems such as fixed-bed columns, adsorption-membrane hybrids, magnetic composites, and gel matrices have been explored to improve operational stability, pollutant removal, and ease of recovery. Summary This review underscores the potential of OPW-derived adsorbents as sustainable and cost-effective alternatives for industrial wastewater treatment. The incorporation of OPW-based materials into engineered systems and the evaluation of post-treatment strategies (e.g., regeneration, reuse, safe disposal) demonstrate their applicability for real-world continuous processes. By promoting the valorization of agricultural waste and addressing current pollution control needs, these materials contribute to improved wastewater management, sustainable resource management, and industrial circularity in palm oil–producing regions. The findings offer valuable insights for environmental managers, policymakers, and industries in adopting circular economy practices and eco-friendly pollution control solutions.