Niobium doping enhanced catalytic performance of Mn/MCM-41 for toluene degradation in the NTP-catalysis system.

The destruction of toluene in a dielectric barrier discharge (DBD) reactor with Nb-Mn/MCM-41 had been investigated and compared with X (X = Cu, Ce, Co)-Mn/MCM-41 catalysts. The XRD and TEM result confirms that the metal species were highly dispersed on the MCM-41. The results of XPS, O2-TPD and H2-TPR clearly demonstrate that Nb doping facilitated formation of lattice oxygen (Olatt) and the acid sites, which are all beneficial to catalytic degradation of toluene. Compared to X (Cu, Ce, Co)-Mn/MCM-41, Nb-Mn/MCM-41 had the most contents of Olatt, the most amounts of acid sites and the strongest acidity. Consequently, the catalytic performance tests identify that Nb-Mn/MCM-41 had the best catalytic performance, the highest removal efficiency and CO2 selectivity as well as carbon balance especially at low SIE. These results indicate that Nb was an important promoter improving the activity and CO2 selectivity of Mn/MCM-41 for the decomposition of toluene in NTP-catalysis system.