锰离子价态对锰基脱硝催化剂性能的影响

Influence of the Valence State of Manganese Ion on the Activity of Mn Supported Catalysts for Denitration

采用选择性溶解和计算相结合的方法,对MnO、MnO2、Mn2O3和Mn3O4的平均价态进行分析,相对误差不超过0.58%。同时,利用此方法可以快速测定MnOx/TiO2催化剂中Mn2+、Mn3+和Mn4+的含量、分布规律及其平均价态。研究表明,当Mn/Ti=0.4、Mn(AC)2为前驱体时,SCR催化剂的脱硝性能最好。此催化剂中的MnOx平均价态较低,这有利于对NO或NH3的吸附,促进脱硝过程的进行。

The average valences of manganese in pure MnO, MnO2, Mn20a and Mna 04 were calculated by the method integrating the selective dissolution with the calculation. The average relative error was not more than 0. 58%. In addition, the content and distributions of Mne＋ , Mna＋ and Mn4＋ as well as the average valences of manganese in catalysts were test ed with the method. According to the results, catalysts that were prepared by MA enhanced the best selective catalytic re duction （SCR） activity, when Mn/Ti atomic ratio was 0. 4. The low average valence of manganese included in the catalysts promoted the adsorbing of NO or NHa and was beneficial to the SCR process.