摘要
以Ag/Al2O3为催化剂,采用原位漫反射傅里叶变换红外光谱法研究了SO2对C3H6选择性还原NOx反应的影响.结果表明,SO2在催化剂表面转化为硫酸盐,并且随着硫酸盐累积量的增加,其主要红外特征吸收峰由低波数向高波数漂移.高浓度表面硫酸盐的存在不仅抑制了催化剂表面硝酸盐的生成,而且抑制了硝酸盐与表面烯醇式物种(RCH=CH-O-)或乙酸盐物种进一步反应,生成活泼的反应中间体异氰酸酯(-NCO),这是导致Ag/Al2O3催化剂上C3H6选择性还原NOx活性降低的主要原因.
In situ diffuse reflectance infrared Fourier transform spectroscopy （DRIFTS） was used to investigate the effect of SO2 on the selective catalytic reduction （SCR） of NOx by C3H6 over an Ag/Al2O3 catalyst. The DRIFTS spectra showed an obvious blue shift in the band of sulfate species when its coverage over Ag/Al2O3 was increased. The sulfate species not only inhibited the formation of NO3^-, but also suppressed the reaction of enolic species or acetate species with NO3^- to form -NCO species. These behaviors are responsible for the deactivation of Ag/Al2O3 during the SCR of NOx by C3H6 in the presence of SO2.
出处
《催化学报》
SCIE
CAS
CSCD
北大核心
2006年第5期403-408,共6页
基金
国家杰出青年科学基金资助(20425722)
关键词
银
氧化铝
氮氧化物
二氧化硫
丙烯
选择性催化还原
原位漫反射傅里叶变换红外光谱
硫酸盐
silver
alumina
nitrogen oxide
sulfur dioxide
propene
selective catalytic reduction, in situ diffuse reflectance infrared Fourier transform spectroscopy
sulfate species
