Enhanced catalytic activity and stability of Cu modified sludge‐derived char catalyst by chemical vapor deposition for toluene oxidation

Abstract BACKGROUND Eco‐friendly and stable catalysts are key factors in catalytic decomposition technology for volatile organic compounds (VOCs). Cu‐based catalysts with more Cu 2+ species and abundant oxygen vacancies exhibit superior catalytic activity in toluene catalytic oxidation. The active component can be uniformly dispersed by chemical vapor deposition (CVD), which can improve the catalytic performance. RESULTS A series of Cu‐based sludge‐derived char catalysts were successfully synthesized by CVD and impregnation (IM). Modern characterization exhibited that 10 wt% Cu‐modified sludge‐derived char prepared by CVD (10Cu/SC‐CVD) showed a shaggy surface with crystallite size, which offered uniformly dispersed active sites compared with Cu‐loaded ZSM‐5. The excellent catalytic activity of 10Cu/SC‐CVD afforded 50% and 90% toluene conversions at 259 and 304 °C, respectively, which was ascribed to the higher Cu 2+ surface content, abundant oxygen vacancies and superior redox activity. In addition, the results of stability tests demonstrated that 10Cu/SC‐CVD showed excellent catalytic stability for 50 h, while after 42 h of reaction over the IM catalyst, the conversion of toluene slightly declined from 90% to 72%. CONCLUSION Abundant oxygen vacancies, superior oxygen activation ability, excellent redox properties and good stability demonstrate that the prepared Cu‐modified sludge‐derived char catalyst has excellent potential for VOC decomposition in industry. © 2025 Society of Chemical Industry (SCI).