A critical review on carbon materials from oil sludges: Activation, application and future prospects

Abstract The resource recovery and high‐value utilization of oil sludge (OS) have recently received increasing attention. Rich in carbon and various active components, OS is regarded as an ideal precursor for carbon material production. This review summarizes recent progress in the preparation and application of oil sludge‐based carbon materials (OSBC). It compares physical and chemical activation methods, emphasizing that chemical activation more effectively enhances surface area, porosity, and efficiency at lower temperatures. Combined physical and chemical activation also demonstrates synergistic improvements. OSBC has exhibited excellent performance in adsorption and catalysis. Its adsorption capacity for organic pollutants, heavy metals, and CO 2 is influenced by pore structure, surface chemistry, pollutant concentration, and operational conditions. In catalysis, OSBC shows strong performance in persulfate activation, organic degradation, heavy oil cracking, and oxygen reduction reactions. Its catalytic efficiency and selectivity can be further enhanced by nanoparticle loading and heteroatom doping. It aims to provide new insights into the resource‐reused and high‐value utilization of OS. It also discusses the current challenges and future directions for OSBC development, aiming to support the sustainable and efficient use of OS.