Insight into the Synergetic Effects of NTP-La<sub>1–<i>x</i></sub>Ag<sub><i>x</i></sub>MnO<sub>3</sub> on Soot Oxidation at Low Temperatures
He Sun, Feiyang Zhang, Shixin Liu, Yangyang Liu, Bin Zhu, Xuehua Yu, Zean Xie, Zhen Zhao
Abstract
Nonthermal plasma (NTP)-assisted catalysis technology is proposed to enhance the rate of catalytic soot combustion at low temperatures. This study evaluated the performance of NTP technology combined with silver-doped La 1– x Ag x MnO 3 on the catalytic soot combustion under simulated conditions of 10% oxygen and at 200 °C. Results showed that a combination of NTP and La 0.5 Ag 0.5 MnO 3 had a super strong synergetic effect below 200 °C and thus led to a much higher rate of soot combustion than the simple additive effect of NTP and a bare catalyst. In the dry gas flow or low water vapor content, the best catalytic behavior for soot combustion was obtained at low reaction temperatures under loose contact between soot and the catalyst, i.e., more than 90% soot conversion and CO 2 selectivity were simultaneously achieved using NTP-La 0.5 Ag 0.5 MnO 3 hybrid for soot oxidation at 200 °C. Even at 10 vol % water vapor content, soot conversion was still 83%, and the CO 2 selectivity was more than 90%, indicating that La 0.5 Ag 0.5 MnO 3 possesses good water resistance. Based on a series of comparative studies, the synergetic mechanism of NTP-La 1– x Ag x MnO 3 synergetic catalysis at low temperatures was proposed.