Promotional effect of zirconium additives on Ti0.8Ce0.2O2 for selective catalytic reduction of NO

Abstract

Flue gas denitrification has been a worldwide topic to build a low carbon society. In view of its high efficiency, high stability, mature technology and large amount of flue gas treatment, selective catalytic reduction (SCR) has been the most promising approach for removing NO_x. As the core of the SCR technology, the catalyst has been attracting wide attention. In particular, developing a novel metal oxide denitrification catalyst with merits of high efficiency, low cost and being environmentally friendly has become an emerging research topic for environmental protection. The TiO₂–CeO₂ complex oxides reveal optimal catalytic performance and are considered by many as an excellent catalytic material for future SCR of NO_x. In order to further enhance its anti-poisoning ability and optimize the catalytic stability of the TiO₂–CeO₂ complex oxides in denitrification, the promotional effect of a zirconium additive on the catalytic performance of the representative Ti_0.8Ce_0.2O₂ for NH₃-SCR of NO is systematically studied for the first time in the present work. Results show that zirconium additives not only dramatically improve the catalytic activity and N₂ selectivity, but also significantly enhance the anti-sulfur ability. The promotional mechanism indicates that the improving effects are not induced by variation of specific surface area, but are caused by other reasons relating to redox properties, microstructure, and surface acidity of the catalyst.