| In this paper wide-temperature low shift Cu-Zn-Cr 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 to low shift Cu-Zn-Cr catalyst were investigated. The results show that the catalyst exhibits highest catalystic activity while the ration of Cu-Zn-Cr, the concentration of mixed solution neutralized, modulated temperature, modulated time, pH value and calcination temperature are 12:17:57, 1mol/L,70～80℃,40min, 7.5～9.0,450℃and 3h respectively. Moreover, the heat resistance of as-prepared catalyst remarkably increases while the promoter are composed of 0.8% Ce,0.6% La. In addition, the catalyst has great adapability to low water-gas rate, even the rate to 2, still no by-product is found.The influences of preparation parameters (precipitation, temperature, precipitate way, calcined temperature, GHSV, reduction gases) on the catalytic activity of Cu-Zn-Cr catalyst were investigated. The catalytic activity of Cu-Zn-Cr catalyst were the best when the precipitator is Na2CO3, the base to sale sample calcined at 450℃for three hours, reduce gas is CO and H2.The obtained catalyst was characterized by XRD, TG-DTA, BET, TPR and TEM testing technologies. The analysis results show that the ideal catalyst is composed of Cu-Zn-Cr and solid-solution-state, as well as some amorophous substances. In the catalyst, Cu is major activity component, and Zn can stabilize CuO. The particle diameter is small and uniform, and the surface area of catalyst is about 64.7277m2/g. The result of XRD indicated that the addition of rare earth in CuO-ZnO-Cr2O3 can not transform the crystalling phase of the catalyst. The thermal stability of CuO-ZnO-Cr2O3 is improved when the addition of rare earth.
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