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采用共沉淀-程序升温焙烧的方法制备Cu/Mn氧化物催化剂,考察元素组成对催化剂结构和性能的影响.通过扫描电子显微镜(SEM)、X射线衍射仪(XRD)、比表面积分析仪(BET)等对样品进行表征.结果表明,催化剂前驱体在程序升温焙烧过程中可形成Cu_(1.5)Mn_(1.5)O_4尖晶石相,该尖晶石相结构有利于Cu晶粒分散,防止Cu晶粒在反应过程中团聚和烧结.元素组成显著影响催化剂的前驱体结构和性能.当Cu占Cu、Mn总质量的40%时,催化剂前驱体中几乎全部的Cu都与Mn结合形成Cu_(1.5)Mn_(1.5)O_4尖晶石相,比表面积最大,催化活性最高,CO_2转化率最高达到16.3%.尖晶石相结构有利于催化剂活性提高.Cu/Mn氧化物催化剂更有助于促进逆水煤气变换(RWGS)反应.
Cu / Mn oxide catalysts were prepared by coprecipitation-temperature programmed calcination to investigate the effect of elemental composition on the structure and properties of the catalysts. The effects of elemental composition on the structure and properties of the catalysts were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD) ) Were used to characterize the samples.The results show that the catalyst precursor can form Cu_ (1.5) Mn_ (1.5) O_4 spinel during the process of temperature programmed calcination.The phase structure of the spinel is conducive to the dispersion of Cu grains, When the Cu accounts for 40% of the total mass of Cu and Mn, almost all of the Cu in the catalyst precursor combines with Mn to form Cu_ ( 1.5) Mn_ (1.5) O_4 spinel phase has the highest specific surface area, the highest catalytic activity and the highest CO 2 conversion rate of 16.3%. The spinel phase structure is favorable for the catalyst activity. The Cu / Mn oxide catalyst is more helpful to promote Reverse Water Gas Shift (RWGS) reaction.