CeO2与WO3协同作用对CeO2-WO3催化剂脱硝性能影响的研究

CeO₂与WO₃协同作用对CeO₂-WO₃催化剂脱硝性能影响的研究

摘要: 采用原位自组装法分别制备纯CeO₂、WO₃和CeO₂-WO₃（CW）催化剂，并研究其NH₃选择性催化还原NO_x的催化活性。结果表明，WO₃的加入使得CW催化剂以微孔为主且具有最大的孔容和较大的比表面积，提高了其催化性能。WO₃的加入增强了Ce和W之间的相互作用，显著地提升了Ce³⁺和O_α的含量。CW催化剂具有最多的酸性位点。因此，CW催化剂催化活性最好，在250-400 ℃温度下NO_x转化率为100%。

Abstract: The CeO₂, WO₃ and CeO₂-WO₃ (donated as CW) catalysts were prepared by in-situ self-assembly method and used for the low-temperature selective catalytic reduction (SCR) of NO_x with NH₃. The results showed that CW catalysts possessed the most microspore and maximum pore volume and larger specific surface area with the addition of WO₃, resulting in the improvement to the catalytic performance. Besides, the interaction of Ce and W was improved by the introduction of WO₃, which could increase the amount of Ce³⁺ and O_α. Meanwhile, the enhancement of weak and medium strong acid sites was caused by the introduction of WO₃. Thus, CW catalyst showed the best SCR activity and its NO_x conversion at the value of 100% maintained in a wide temperature window ranging from 250 to 400 ℃.