Remarkable enhancement in the N 2 selectivity of NH 3 -SCR over the CeNb 3 Fe 0.3 /TiO 2 catalyst in the presence of chlorobenzene

The simultaneous removal of NO and dioxins is the frontier of environmental catalysis, which is still in the initial stage and poses several challenges. In this study, a series of CeNb Fe /TiO (x = 0, 0.3, 0.6, and 1.0) catalysts were prepared by the sol-gel method and examined for the synergistic removal of NO and CB. The CeNb Fe /TiO catalyst exhibits an optimum catalytic performance, with an NO conversion greater than 95% at 260-380 °C. It also exhibits an optimal CB oxidation activity, in which CB promoted both the NO conversion and N selectivity below 250 °C. Moreover, the more favorable ratios of Ce to Ce and plentiful surface-adsorbed oxygen species are the reasons why CeNb Fe /TiO catalyst has better catalytic activity than other catalysts at the lower temperature. Simultaneously, owing to the modulation of Fe to the redox properties of Ce and Nb, the large number of oxygen vacancies and acid sites was generated, and the CeNb Fe /TiO catalyst is beneficial to NO reduction and CB oxidation. Furthermore, the results of in situ DRIFTS study reveal the NH -SCR reactions over CeNb Fe /TiO catalysts are mainly conformed to by the L-H mechanism ( 350 °C), respectively, and the multi-pollutant conversion mechanism in the synergistic reaction was systematically studied.