|Journal||Journal of hazardous materials, 2020-01-15, Volume 382 Find other publications in this journal|
The CeO catalysts grafted with heteropoly acid (i.e., HPA) could enhance their catalytic performance for selective catalytic reduction of NO with NH (NH-SCR). In comparison to HSiW/CeO, HPMo/CeO, and commercial VO-WO/TiO catalysts, HPW/CeO catalysts showed the best SCR performance. XPS and DRIFTS demonstrated that the amount of HPA on HPW/CeO was more than those on HSiW/CeO and HPMo/CeO. H-TPR results indicated that reducibility of HPMo/CeO was stronger than those of HSiW/CeO and HPW/CeO, resulting in the high-temperature performance loss. According to kinetic results, below 250 °C, k and k of HPW/CeO were higher than those of HSiW/CeO, meanwhile k of both HSiW/CeO and HPW/CeO were low. Therefore, HPW/CeO had the better SCR performance than HSiW/CeO. As NH was completely consumed, SCR activity depended on the ratio of SCR reaction in the consumption of NH. The selectivity of SCR reaction, NSCR reaction, and C-O reaction of HSiW/CeO were almost the same as those of HPW/CeO above 250 °C, resulting in the NO conversion of HPW/CeO was basically the same as that of HSiW/CeO above 250 °C. Due to the lowest k and k, and highest k, NO conversion of HPMo/CeO was the worst compared to HSiW/CeO and HPW/CeO catalysts.