The self-protection effect of reactant gas on the moisture stability of CuSAPO-34 catalyst for NH3-SCR

被引：23

作者：

Cao, Yi ^{[1
]}

Fan, Dong ^{[1
]}

Sun, Lijng ^{[1
,2
]}

Yang, Miao ^{[1
]}

Cao, Lei ^{[1
]}

Sun, Tantan ^{[1
,2
]}

Xu, Shutao ^{[1
]}

Tian, Peng ^{[1
]}

Liu, Zhongmin ^{[1
]}

机构：

[1] Chinese Acad Sci, Dalian Inst Chem Phys, Dalian Natl Lab Clean Energy, Natl Engn Lab Methanol Olefins, Dalian 116023, Peoples R China

[2] Univ Chinese Acad Sci, Beijing 100049, Peoples R China

来源：

CHEMICAL ENGINEERING JOURNAL | 2019年 / 374卷

基金：

中国国家自然科学基金; 中国博士后科学基金;

关键词：

CuSAPO-34; Stability; Residual adspecies; Self-protection; NH3-SCR; DEACTIVATION MECHANISM RESEARCH; HYDROTHERMAL STABILITY; CU/SAPO-34; CATALYSTS; CU-SAPO-34; BRONSTED ACIDITY; NOX; REDUCTION; COPPER; NH3; AMMONIA;

D O I：

10.1016/j.cej.2019.05.227

中图分类号：

X [环境科学、安全科学];

学科分类号：

08 ; 0830 ;

摘要：

The surface of CuSAPO-34 catalysts after NH3-SCR reaction (T <= 400 degrees C) is revealed to have residual adspecies. Cycle hydration methods are designed to explore the influence of the residual species upon the moisture stability of CuSAPO-34. It is demonstrated that the residual species on the catalyst surface are NH3 adspecies, which could help inhibit the transformation of Si(OAl)(4) species to Si islands and prevent the decay of Bronsted acid sites (BAS) during the hydration treatment; the better preserved acidity and the existence of NH3 facilitate the preservation of isolated Cu2+ ions and their reducibility, and thus the SCR activity of the catalysts. The protective effect of residual NH3 species against the low-temperature water vapor is prominent when T <= 300 degrees C, which declines gradually and becomes weak when T > 400 degrees C due to the desorption of NH3 adspecies. The present work implies that the moisture stability of CuSAPO-34 catalyst could be simply ameliorated by locating it in an appropriate zone of the tailpipe to avoid the excessive desorption of the NH3 adspecies.

引用

页码：832 / 839

页数：8

共 33 条

[1] Impact of SCR Integration on N2O Emissions in Diesel Application [J].