Comparative study of copper-based catalysts supported by ceria, zirconia and alumina for volatile organic compounds removal

The emission of volatile organic compounds (VOCs) such as toluene and furfuryl alcohol from industrial activities and biomass combustion contributes significantly to air pollution and human health risks. Catalytic oxidation is considered one of the most effective approaches for VOC removal at low temperatures. In this study, copper-based catalysts supported on ceria (CeO 2 ), zirconia (ZrO 2 ) and alumina (Al 2 O 3 ) were synthesised via the wet impregnation method to investigate the influence of support materials on VOC oxidation performance. The catalysts were characterised using XRD, BET, TEM, XPS, NH 3 -TPD, H 2 -TPR and O 2 -TPD analyses. Results showed that CuO x -CeO 2 exhibited the smallest crystallite size, highest lattice oxygen ratio and superior redox properties compared with CuO x -ZrO 2 and CuO x -Al 2 O 3 . The CuO x -CeO 2 catalyst also demonstrated the highest specific surface acidity and oxygen mobility, which enhanced the oxidation of toluene and furfuryl alcohol. The strong metal-support interactions between CuO and CeO 2 facilitated greater dispersion of copper species and improved the redox equilibrium between Cu 2+ and Cu + ions. Post-characterisation of the spent catalysts confirmed high structural stability after reaction. These findings highlight the importance of selecting suitable supports to optimise the physicochemical properties and catalytic activity of copper-based catalysts for efficient VOC oxidation. • Catalyst support selection strongly influences redox behaviour and oxygen mobility. • CuO x -CeO 2 shows superior VOC oxidation compared with ZrO 2 and Al 2 O 3 supports. • CuO x -CeO 2 demonstrates high stability during long-term VOC oxidation. • High lattice oxygen concentrations enhance Mars-van Krevelen mechanism. • Strong Cu-Ce interaction improves dispersion and Cu 2+ /Cu + redox cycling.