Simultaneous Removal of NO<sub><i>x</i></sub> and CO over CoMnO<sub><i>x</i></sub>: Promotional Effect and Mechanism of MnO<sub><i>x</i></sub>
Chunyi Bian, Guizhen Zhang, Cui Liu, Shilin Deng, Liyun Song, Zongcheng Zhan, Jian Li, Hong He
Abstract
A chemical coprecipitation method was used to synthesize the CoMnO x oxides for simultaneous ammonia selective catalytic reduction (NH 3 -SCR) and CO oxidation. The physicochemical characterization results showed that adding MnO x gave an enhancement of acidity, pore structure, and redox properties on the Co 3 O 4 catalyst, which improved the synergistic removal of NO x and CO. The NO conversion of CoMnO x catalysts exceeded 95%, and the CO conversion exceeded 88% at 120–160 °C. The in situ DRIFT spectra suggested that NH 3 -SCR and CO oxidation reactions are reciprocally inhibited over Co 3 O 4 . MnO x added provided more Lewis acid sites on the Co 3 O 4 catalyst to participate in the SCR reaction, which alleviated the inhibitory effect of CO for NO reduction by NH 3 .