钒酸盐络合剂对V_2O_5 /TiO_2 SCR催化剂织构和催化性能的影响

Using commercial anatase TiO₂ as a support, V₂O₅/TiO₂ catalysts with three different vanadate complexing agents were prepared by the impregnation method, and the effects of different vanadate complexing agents on the SCR reactions of these three catalysts were investigated. The valence states and pH values of vanadium complexes in the precursor solutions, as well as the catalyst samples, were characterized by H₂-TPR, BET specific surface area and pore structure characteristics, NH₃-TPD, XRD, Raman spectroscopy, ultraviolet, etc. It was found that different complexing agents can affect the valence states of vanadates in the precursor solutions and also affect the pH values of the precursor solutions. However, within the test temperature range, there were no significant differences in the activity and N₂ selectivity of the SCR reactions of these three catalysts. Through different characterization methods, it can be known that there are no significant differences in the specific surface area, pore structure, polymerization degree of surface vanadium oxides, activation energy of H₂ reaction, and acid amount on the catalyst surface of the catalysts. The valence states and pH values of vanadium complexes in the precursor solutions have no significant impact on the catalytic performance of the SCR reactions of the catalyst samples.

以商业锐钛矿型TiO_2为载体,通过浸渍法制备了3种不同钒酸盐络合剂的V_2O_5 /TiO_2催化剂,并考察不同钒酸盐络合剂对该3种催化剂SCR反应的影响。对前驱体溶液的钒配合物价态、pH值,以及对催化剂样品进行H_2-TPR、 BET比表面积和孔结构特征、NH_3-TPD、XRD、拉曼光谱、紫外等表征。研究发现,不同络合剂会影响钒酸盐在前驱体溶液中的价态,同时影响前驱体溶液的pH值,但是在测试温度范围内,该3种催化剂的SCR反应在活性和N_2选择性均无明显区别。通过不同的表征方法可知:催化剂的比表面积、孔结构、表面钒氧化物的聚合程度、H_2反应活化能、催化剂表面酸量均没有明显区别,前驱体溶液中钒配合物的价态和pH值对催化剂样品的SCR反应催化性能没有明显影响。