Synergistic catalysis of NO and chlorobenzene over Mn3O4-CeO2 catalysts: Acid sites, catalytic pathway and mechanism

Catalyst active sites and surface acidity are crucial for the synergistic catalysis of NOx x and dioxins, determining the selectivity towards N2 2 and CO2. 2 . This study synthesized Mn3O4-CeO2 3 O 4-CeO 2 catalysts to investigate the influence of these sites on the catalytic performance for NO and chlorobenzene. Mn0.086Ce, 0.086 Ce, made by the redox method, showed the highest Mn-Ce interface, achieving nearly complete conversion of chlorobenzene and NO at 180 degrees C, with CO2 2 and N2 2 selectivity reaching about 80 % and 100 %, respectively. EPR, NH3-TPD 3-TPD and Py-IR analyses revealed that the Mn-Ce interface induces the formation of Lewis acid sites and oxygen vacancies, facilitating the adsorption and conversion of chlorobenzene, NH3, 3 , and NO. Mn adjacent to Lewis acid sites is the main active site, while Ce acts as an electron transfer agent. Based on the results of in-situ DRIFTS and TOF-SIMS, the possible degradation pathway for chlorobenzene was proposed and as follows: phenol, benzoquinone, maleic anhydride, propionic acid, CO2, 2 , and H2O. 2 O. The NH3-SCR 3-SCR reaction follows the Eley-Rideal mechanism at 150-300 degrees C.