溶液燃烧法制备TiV_(0.1)Mn_(0.1)Er_(0.01)O_x催化剂催化还原NO_x的性能研究

为了拓宽选择性催化还原NO_x钒基催化剂的活性温度窗口,采用溶液燃烧合成法制备了TiV_(0.1)O_x催化剂,依次加入Mn元素与Er元素形成新的催化剂,分别对它们进行了SCR活性及选择性测试,发现负载Mn元素可以提高钒基催化剂的低温活性,同时也会降低钒基催化剂的高温活性,负载适量的Er元素可以提高钒基催化剂的高温活性和N_2选择性。利用N2吸附脱附法进行BET比表面积和孔容孔径分析,发现负载Er元素增大了比表面积,进而提升了催化剂活性。利用X射线衍射(XRD)图谱进行晶体结构分析,所有催化剂样品均没有发现VO_x,MnO_x或ErO_x的衍射峰,说明溶液燃烧法制备的催化剂活性组分在TiO2颗粒上呈无定型态分布,分散度高。最终优选出最佳Mn和Er比例的TiV_(0.1)Mn_(0.1)Er_(0.01)O_x催化剂,在160~470℃之间保持80%以上的NO_x去除率。

NOx Removal Performance of TiV0.1Mn0.1Er0.01Ox Catalyst Prepared by Solution Combustion Method

In order to expand the active temperature window of vanadium-based catalysts, TiV0.1Ox catalyst was prepared with the solution combustion method.New catalysts were formed by adding manganese and erbium element successively, the activity and selectivity of each catalyst were evaluated respectively.The experimental results showed that manganese increased the low temperature activity of vanadium-based catalysts and decreased its high temperature activity.Erbium increased the high temperature activities of vanadium-based catalyst and improved N2 selectivity.BET specific surface area, hole volume and hole diameter were analyzed with N2 adsorption and desorption method, it was found that erbium increased the specific area of vanadium-based catalysts to promote the activity of catalyst.The XRD patterns of crystal structure showed that the diffraction peaks of VOx, MnOx or ErOx metal oxides didnot exist, showing that active components were uniformly dispersed on the surface of all the catalysts prepared by solution combustion method.The prepared TiV0.1Mn0.1Er0.01Ox catalyst according to the proportion of manganese and erbium had the best performance of over 80% NOx removal efficiency between 160 ℃ and 470 ℃.