Modulating multi-active sites in CeO2-modified MnOx/ZSM-5 catalyst for selective catalytic oxidation of diethylamine

An efficient MnO x /CeO 2 /ZSM-5 catalyst was developed for selective oxidation of diethylamine (DEA) with high N 2 selectivity in a wide temperature window ( Δ T = 140 °C), owing to the existence of oxidation and selective catalytic reduction (SCR) active sites. MnO x species prefer to locate on the surface of CeO 2 compared to ZSM-5, and the presence of CeO 2 is beneficial to form more Mn 4+ species, the active sites for oxidation reaction. The mechanistic investigation suggests that internal SCR of NO x generated from the over-oxidized DEA is the crucial pathway for N 2 generation. The high SCR activity of the MnO x /CeO 2 /ZSM-5 catalyst in oxidation conditions is mainly attributed to the synergistic catalysis of Mn 4+ species and acid sites of ZSM-5, the active sites for SCR reaction. Thus, it has been clearly clarified that addition of CeO 2 and its addition sequence could modulate the surface active sites of MnO x /ZSM-5 catalyst for the selective catalytic oxidation of DEA.