Remarkable Enhancement In The N2- Selectivity of NH3-SCR Over The CeNb3Fe0.3/TiO2 Catalyst In The Presence of Chlorobenzene

The simultaneous removal of NO x 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 3 Fe x /TiO 2 (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 x and chlorobenzene. The CeNb 3 Fe 0.3 /TiO 2 catalyst exhibits an optimum catalytic performance, with an NO x conversion greater than 95 % at 260-380 °C. It also exhibited an optimal CB oxidation activity, in which CB promoted both the NO x conversion and N 2 selectivity below 250 °C. Moreover, the more favourable ratios of Ce 4+ to Ce 3+ , and plentiful surface adsorbed oxygen species are the reasons why CeNb 3 Fe 0.3 /TiO 2 catalyst has better catalytic activity than other catalysts at 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, the CeNb 3 Fe 0.3 /TiO 2 catalyst is is beneficial to NO x reduction and CB oxidation. Further, the results of in situ DRIFTS study reveal the NH 3 -SCR reactions over CeNb 3 Fe x /TiO 2 catalysts are mainly controlled by the L-H mechanism ( 200 °C), respectively.