Abstract: A series of Cu/SAPO-34 and Cu-Ce/SAPO-34 catalysts with different loadings are prepared by impregnation method.The effects of Cu and Ce loadings on the performance of the catalysts are investigated.Experimental results show that Cu/SAPO-34 catalyst with a 4% of loadings has excellent NH3-SCR performance,over which the conversion efficiency can exceed 80% in the temperature range of 231-586℃,and the highest denitration efficiency reaches 98.79%.By co-loading transition metals Cu and Ce,the performance of the catalyst in medium-low temperature NH3-SCR is improved,and the activity temperature window of the catalyst is broadened.XRD and H2-TPR characterization shows that Ce doping can inhibit the formation of CuO and promote the formation of Cu2+ with higher activity.NH3-TPD characterization shows that higher Cu loadings can increase the number of acid sites of Cu/SAPO-34 catalyst.Ce doping may occupy B acid position of the molecular sieve carrier,resulting in a decrease in the number of medium-strength acid sites of the catalyst.Therefore the optimum doping amount of Cu/Ce is 4:5.
胡宜康, 徐斌, 曹智焜, 毛静雯. Cu负载量及改性对Cu/SAPO-34催化剂NH3-SCR性能的影响[J]. 现代化工, 2020, 40(5): 122-127.
HU Yi-kang, XU Bin, CAO Zhi-kun, MAO Jing-wen. Effect of Cu loading amount and modification on NH3-SCR performance of Cu/SAPO-34 catalysts. Modern Chemical Industry, 2020, 40(5): 122-127.
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