摘要
在TiO2负载的锰氧化物(MnOx/TiO2)中引入第2种组分,制成二元金属氧化物(MnOx-A/TiO2)催化剂,A分别为Fe2O3、WO3、MoO3、Cr2O3,试验研究低温催化活性、N2选择性及抗SO2毒性。结果表明,低温催化活性从高到低依次为:Mn-W/TiO2>Mn-Fe/TiO2>Mn-Cr/TiO2>Mn-Mo/TiO2;N2选择性:Mn-Fe/TiO2>Mn-W/TiO2>Mn-Mo/TiO2>Mn-Cr/TiO2,Mn-Fe/TiO2和Mn-W/TiO2保持了较高低温催化活性的同时提高了N2选择性。当反应气中含有&(SO2)=0.01%和&(H2O)=6%,空速为12600h-1、120℃、8h后NOx转化率Mn-W/TiO2、Mn-Fe/TiO2、Mn-Mo/TiO2分别保持在98.5%、95.8%及94.2%。由此得出,WO3、Fe2O3为MnOx有效的助催化剂,可大大提高MnOx/TiO2的选择性和抗SO2毒性的能力。傅里叶变换红外光谱显示,与Fe2O3不同,WO3也提供了部分Lewis酸活性点,说明在有低浓度SO2存在下,Mn-W/TiO2显示了极好的低温NH3选择性还原NOx的催化活性。
The manganese-based binary metal oxides supported on titanium dioxide （MnOx-A/TiO2） were prepared, where A means Fe2O3, WO3, MoO3 and Cr2O3. Their catalytic activity, N2 selectivity and SO2 poisonous tolerance were investigated. The catalytic performance at low temperature decreased in the following order： Mn-W/TiO2〉Mn-Fe/TiO2〉 Mn-Cr/TiO2〉Mn-Mo/TiO2, while N2 selectivity： Mn-Fe/TiO2〉 Mn-W/TiO2〉Mn-Mo/TiO2〉Mn-Cr/TiO2. In presence of 0.01% SO2 and 6% H2O, the NOx conversion of Mn-W/TiO2, Mn-Fe/TiO2, Mn-Mo/TiO2 maintained 98.5%, 95.8% and 94.2% respectively after 8 h at 120 ℃ at GHSV 12 600 h^-1. As effective promoters, WO3 and Fe2O3 can increase N2 selectivity and the resistance to SO2 of MnOx/TiO2 significantly. The Fourier transform infrared spectrum （FT-IR） spectra of NH3 showed that unlike Fe2O3, WO3 also provides part of Lewis acid sites. In presence of low concentration of SO2, Mn-W/ TiO2 exhibited excellent catalytic performance for low temperature selective catalytic reduction of NO with NH3.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2008年第23期75-80,共6页
Proceedings of the CSEE
关键词
NH3选择性催化还原NO
低温选择性催化还原
二元金属氧化物
傅里叶变换红外光谱
氨程序升温脱附
selective catalytic reduction of NO with NH3
low-temperature selective catalytic reduction
binary metal oxides
Fourier transform infrared spectrum
NH3 temperature programmed desorption
