Mesoporous silica-pillared clays supported nanosized Co3O4-CeO2 for catalytic combustion of toluene

Abstract Mesoporous silica-pillared clay (SPC) was synthesized by a soft template method. Compared with the raw montmorillonite (MMT), the basal spacing of SPC increased from 0.96 to 2.61 nm, the specific surface area increased from 30 to 453 m 2 /g, and the thermal stability was also improved, all of which could reduce the mass transfer resistance and improve the adsorption capacity of toluene. SPC supported Co 3 O 4 and rare earth (Y, La, Ce, Pr and Nd) nano-composite catalysts were prepared by a deposition-precipitation method. Among them, 10% Co-5% Ce/SPC displayed the highest catalytic combustion activity, and the reaction temperature for toluene combustion was about 200 °C (98% conversion). This catalyst displayed good durability, and conversion of toluene dropped slightly from 96% to 90% in 1000 h continuous reaction at 190 °C. Co 3 O 4 and CeO 2 had particle sizes of 5–8 nm and were dispersed homogeneously on the surface of SPC. Introduction of CeO 2 enhanced oxygen storage/transport capacity, and improved the dispersion of Co 3 O 4 on SPC. The interaction of Co 3 O 4 -CeO 2 and SPC, the co-existence of Co 2+ /Co 3+ and the higher concentration of Ce 3+ ions on the catalyst surface contribute to the high catalytic oxidative activity of 10% Co-5% Ce/SPC for toluene combustion.