Catalytic Oxidation of Acetone on SmMn₂O₅: Effect of Acid Etching and Loading Treatment

The key of catalytic oxidation technology is to develop a stable catalyst with high activity. It is still a serious challenge to achieve high conversion efficiency of acetone with an integral catalyst at low temperature. In this study, the SmMn2O5 catalyst after acid etching was used as the support, and the manganese mullite composite catalyst was prepared by loading Ag and CeO2 nanoparticles on its surface. By means of SEM, TEM, XRD, N2-BET, XPS, EPR, H2-TPR, O2-TPD, NH3-TPD, DRIFT, and other characterization methods, the related factors and mechanism analysis of acetone degradation activity of the composite catalyst were discussed. Among them, the CeO2-SmMn2O5-H catalyst has the best catalytic activity at 123 and 185 °C for T50 and T100, respectively, and shows excellent water and thermal resistance and stability. In essence, the surface and lattice defects of highly exposed Mn sites were formed by acid etching, and the dispersibility of Ag and CeO2 nanoparticles was optimized. Highly dispersed Ag and CeO2 nanoparticles have a highly synergistic effect with the support SmMn2O5, and the reactive oxygen species provided by CeO2 and the electron transfer brought by Ag further promote the decomposition of acetone on the carrier SMO-H. In the field of catalytic degradation of acetone, a new catalyst modification method of high-quality active noble metals and transition metal oxides supported by acid-etched SmMn2O5 has been developed.