| In this paper, high temperature water-gas shift Cu-based Mn catalyst was prepared by co- precipitation method. The technology conditions of catalyst preparation, types and amounts of promoter were detail studied. And the effects of promoters on heat resistance, adaptibility to low water gas rate of catalyst were principally investigated, and the influence reactor size was also discussed. The results show that the catalyst exhibits highest catalystic activity while the ration of Cu to Mn, the concentration of mixed solution neutralized, modulated temperature, modulated time, pH value and calcination temperature are 0.5, 0.10 g/mL, 45 °C , 9 min, 11.5, 550 °C and 4 h, respectively. Moreover, the heat resistance of as-prepared catalyst remarkably increases while the promoter are composed of 2.0 % CeO2, 2% LaO2, and 1.5 % K2O. In addition, the catalytic activity of prepared catalyst is still above 67.5 % after the catalyst was measured on the condition of standard measurement of high temperature water-gas shift catalyst, and the catalyst has great adapability to low water-gas rate, even the rate lowers to 0.3, still no by-product is found.The reactor dimensions can influence activity, heat resistance and micro-structure of catalyst in some degree. The macro-reaction process can change the catalyst performances by means of added influences on microenvironments, such as supersaturation degree, micro-crystallized process.The obtained catalyst was characterized by XRD, TG-DTA, N4 Plus and TEM testing technologies. The analysis results show that the ideal catalyst is composed of Cu, Mn and solid-solution-state promoter, as well as some amorophous substances. In the catalyst, Cu is major activity component, and Mn can stablize CuO. The particle diameter is mainly in the range from 400 to 700 run, and the surface area of catalyst is about 25.0276 m2/g. The obtained catalyst has higher catalytic activity compared with Fe-base catalyst.
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