文献类型：期刊文献

英文题名：Revealing the mechanism of K-enhanced Cu-SSZ-13 catalysts against hydrothermal aging and P-poisoning for NOx reduction by NH3-SCR

作者：Shen, Yali[1];Dong, Wenwei[1];Zhang, Li[2];Wang, Li[1];Chen, Biao[2];Guo, Yanglong[1];Zhan, Wangcheng[1];Wang, Aiyong[1];Ge, Chunliang[2];Guo, Yun[1]

机构：[1]East China Univ Sci & Technol, Res Inst Ind Catalysis, Sch Chem & Mol Engn, State key Lab green Chem Engn & Ind Catalysis, Shanghai 200237, Peoples R China;[2]Zhejiang Tiandi Environm Protect Technol Co Ltd, Hangzhou 311121, Zhejiang, Peoples R China

年份：2024

卷号：330

外文期刊名：SEPARATION AND PURIFICATION TECHNOLOGY

收录：;EI(收录号：20234014844911);WOS:【SCI-EXPANDED(收录号:WOS:001160004900001)】；

语种：英文

外文关键词：NH3-SCR; Cu-SSZ-13; K-modification; Poisoning tolerance; Hydrothermal aging

摘要：Cu-SSZ-13 (Cu-Z) has been commercialized as an efficient catalyst for NOx removal in mobile sources. However, in practical applications, the catalyst faces problems of poisoning (K and P) and hydrothermal aging. Therefore, in this work, we investigated the effects of K on P poisoning and hydrothermal aging in Al-rich Cu-2/Z (2 wt% Cu). The presence of 1 wt% K could not only improve the high-temperature activity, which could reach above 99% at 225-600 degrees C on the K-1/Cu-2/Z, but also enhanced the hydrothermal stability and the resistance of P poisoning. Combing with a series of characterizations, K was mainly present in the Bronsted acid sites in the CHA cage, which led to the transformation of part of Z-[Cu(OH)](+) to Z(2)-Cu2+, reducing dealumination and the formation of CuOx and CuAl2O4 species during hydrothermal aging. Moreover, the presence of K could inhibit the formation of Cu-PO3-/PO43- species by P poisoning of Z-[Cu(OH)](+) species. In-situ DRIFTS results showed that the catalysts followed both E-R and L-H mechanism at 150 celcius. K doping could promote the formation of nitrate species and thus favoring the L-H mechanism, which probably enhanced the NH3-SCR activity