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制备了由过渡金属M(M=Cr、Mn、V、Fe、Cu、Co)与Zr、Ce氧化物组成的三元选择性催化还原(SCR)催化剂,用低温氮吸附(BET)、X射线衍射分析(XRD)、X射线光电子能谱(XPS)、氨-程序升温脱附(NH3-TPD)、氢-程序升温还原(H2-TPR)等手段表征了样品的比表面和孔结构、晶体结构、元素价态、酸性位类型以及氧化还原能力,研究了催化剂的性能。结果表明,MnZr-Ce三元催化剂的低温(<200℃)活性较好,但是高温(>250℃)活性较差;Cr-Zr-Ce三元催化剂在低温和高温(100-300℃)下性能均比较稳定,V-Zr-Ce三元催化剂在低温(<200℃)下性能较差,但是其高温(300℃左右)活性不断提高。研究了以上3种催化剂的耐硫性,并结合测试结果解释和分析了上述实验现象。
A ternary selective catalytic reduction (SCR) catalyst consisting of transition metal M (M = Cr, Mn, V, Fe, Cu and Co) and Zr and Ce oxides was prepared and characterized by low temperature nitrogen adsorption (BET), X-ray XRD, XPS, NH3-TPD and H2-TPR were used to characterize the specific surface area and pore structure of the samples. Crystals Structure, valence of element, type of acid sites and redox ability were investigated. The results show that the MnZr-Ce ternary catalyst has good low-temperature (<200 ℃) activity but low activity (> 250 ℃). The Cr-Zr-Ce ternary catalyst is stable at low and high temperature (100-300 ℃) The performance of V-Zr-Ce ternary catalyst is poor at low temperature (<200 ℃), but its activity at high temperature (about 300 ℃) is increasing. The sulfur tolerance of the above three catalysts was studied, and the above experimental phenomena were explained and analyzed with the test results.