TiO₂-CeO₂ catalyst is a promising material for removal of NO_x by NH₃-SCR reaction. The poisonous substances existing in flue gas cause serious deactivation of the catalyst. However, most of the researches had focused on the effect of a single toxic component, while the actual flue gas contains multiple toxic components. In this work, the combination of K₂O and PbO poisoning effects on NH₃-SCR performance over the TiO₂-CeO₂ catalyst were investigated. A stronger poisonousness was found when K₂O and PbO were simultaneously introduced. The characterization results showed that the coexistence of K₂O and PbO hinder the transfer of electrons between TiO₂ and CeO₂, and worsen the decrease of surface adsorbed oxygen, the relative ratio of Ce³⁺, as well as the surface acidity. In situ DRIFTS results showed that the decrease of Brønsted acid caused by K and Pb was larger than Lewis acid. Additionally, the combination of K and Pb reduced the activation performance of NO_x species. Finally, the TiO₂-CeO₂ catalyst’s Langmuir-Hinshelwood (L-H) mechanism did not change when K and Pb were introduced.

TiO ₂ -CeO ₂催化剂是通过NH ₃ -SCR反应去除NO _x的有前途的材料。烟气中存在的有毒物质会导致催化剂严重失活。然而，大多数研究都集中在单一有毒成分的影响上，而实际烟气中含有多种有毒成分。在这项工作中，研究了 K ₂ O 和 PbO 中毒对TiO ₂ -CeO ₂催化剂上 NH ₃ -SCR 性能的影响。同时引入K ₂ O 和 PbO时毒性更强。表征结果表明，K₂ O和PbO阻碍了TiO ₂和CeO ₂之间的电子传递，使表面吸附氧、Ce ³⁺的相对比值和表面酸性降低。原位DRIFTS 结果表明 K 和 Pb 引起的布朗斯台德酸的减少大于路易斯酸。此外，K 和 Pb 的组合降低了 NO _x物质的活化性能。最后，当引入 K 和 Pb 时，TiO ₂ -CeO ₂催化剂的 Langmuir-Hinshelwood (LH) 机制没有改变。