Abstract:

A series of Ba and Co doped MnO_x doping catalysts were prepared by citric acid complex method. The effects of Ba and Co doping on the performance of MnO_x low temperature NH₃-SCR were studied. The test results showed that the addition of Ba inhibited the catalytic performance of MnO_x. The Co addition promoted the catalytic performance of MnO_x. When Ba and Co are co-doped, the performance of the catalyst increased obviously. 3BaMnCoO_x showed the most excellent catalytic performance, and the catalytic activity was above 99% when the reaction temperature was higher than 180°C. It showed good water and sulfur resistance. The catalysts were characterized by XRD, SEM, NO-TPD, NH₃-TPD, H₂-TPR and NO adsorption in situ infrared spectroscopy. The results showed that MnCo₂O_4.5 solid solution was formed after Co doping, which guaranteed excellent redox performance. Ba doping provided a new NO adsorption site for the catalyst, which led to the formation of new active nitrate adsorption species. The NO adsorption performance of the catalyst was promoted. These characteristics make BaMnCoO_x low-temperature denitration catalysts show excellent denitration performance.

Key words: adsorption, SCR, experimental validation, Ba addition

摘要：

利用柠檬酸络合法制备了一系列Ba、Co掺入MnO_x脱硝催化剂，研究了Ba、Co掺入对MnO_x低温NH₃-SCR性能的影响。测试结果表明：Ba单独掺入时抑制了MnO_x的催化性能，Co单独掺入时促进了MnO_x的催化性能；而当Ba、Co共掺时，催化剂性能出现了最大的提升，其中3BaMnCoO_x表现出了优异的脱硝活性，反应温度高于180℃时其脱硝性能在99%以上，且表现出了良好的抗水硫性能。采用XRD、SEM、NO-TPD、NH₃-TPD、H₂-TPR和NO吸附原位红外等表征手段对催化剂进行了表征。结果表明，Co掺杂后形成了MnCo₂O_4.5固溶体，赋予了催化剂优异的氧化还原性能；Ba掺杂为催化剂提供了新的NO吸附位点，导致了新的活性硝酸盐吸附物种形成，显著促进了催化剂的NO吸附性能。这些特性使得BaMnCoO_x低温脱硝催化剂展现出了优异的脱硝性能。

关键词: 吸附, 选择性催化还原, 实验验证, 钡掺杂