| The hydrogenation of fatty acid methyl esters to obtain fatty alcohols is a catalytic, multiphase reaction. Conventional technology is carried out in high-pressure reactor, and is expensive in equipment and operation. Therefore in recent years the development of new technique for middle-pressure hydrogenation of fatty acid methyl esters is focused on, therein the catalyst in hydrogenation at middle-pressure is the main technique.Traditional Cu-Cr catalysts may cause serious environmental pollution in preparation, and is facing to be eliminated. Nowadays, the new type of catalyst is not completely mature, and this severely restricts the production of higher fatty alcohols in China. So it has significant meaning to develop a new kind of Cr-free catalyst for higher fatty alcohol production by hydrogenation of fatty acid methyl esters.In this paper a new catalyst was developed, which is more active, non-toxic and non-pollutive and the technology of hydrogenation was studied. The catalysts are prepared by using different elements (e.g. :Cu, Zn,Mn) and were used in hydrogenation of fatty acid methyl esters. The results indicated that the yield of fatty alcohol can be reached 84.2%, when the molar ratio of Cu-Zn-Mn in the catalyst was 4:3:3, the amount of catalyst is 5% (based on the weight of the fatty acid methyl esters) and the reaction temperature, reaction pressure and reaction time were 270℃; 7Mpa and 4 hours, respectively.The measurements of BET surface area; pore distribution and XRD spectrum were used to characterize the catalyst. The results showed that the active phase were copper; zinc oxide and manganese oxide; and the appropriate pore for the hydrogenation of fatty acid methyl esters was at least 10nm, which are consistent with the theoretic analysis.Compared to the traditional Cu-Cr catalysts, Cu-Zn-Mn catalyst is less pollutive in preparation; and the investment of equipments and operating expenses could be reduced using the catalyst in middle-pressure.
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