CuO-ZnO-ZrO2( CZZ) nanocatalysts were successfully prepared by citrate-gel mte hod.The catayl sts and their precursors were characterized by X-ray photoeletc ron spectroscopy ( XP S ) , N2 adsorption specific surface area measurement ( BET ) , X -ray diffraction ( XRD ) , H2-temperature-programmed redutc ion ( H2 -TPR), H2a nd CO2-temperature-programmed desorption ( H2 and CO2-TPD) and thermogravimetric analysis ( TG-DTA ) . Drying time of ht e wet g el and the do sage of citric acid we re syset matci ly studied, while combustion method was also condcu ted wi th the com parison of those obtained catalysts.Resutl s show thta , prolonged drying prco ess can effectively per vent partilc e spattering duir ng calcni ation, benfe it the dispersion of different components in the catalyst, and improve thea dsorpt ion ability of catalyst for H2 and CO2 .Sample CZZ-48 h, which was dried at 112℃, 48 h, maintained a much higher BET specific surface area than that prepared by combustion method.The CuO-ZnO-ZrO2 catalyst, in which 100% of stoichiometric amount of citric acid was added, exhibited an optimum catalytic behavior with a space-time-yield of methanol 109.4 g· h-1· kg-1 under the condition of 240℃, 2.6 MPa, 3 600 h-1 , H2/CO2=3.The detriment of the catalytic performance excessive amounts of citric acid is ascribed to decline dispersion of the catalyst component, and decomposition residual covering on the surface active species of the catalyst.%采用柠檬酸盐凝胶法制备出纳米CuO-ZnO-ZrO2（CZZ）催化剂，应用XPS、BET、XRD、H2-TPR、H2-TPD、CO2-TPD和TG-DTA等检测手段对催化剂及前驱体的结构进行表征。研究了湿凝胶干燥时间和柠檬酸用量对催化剂结构的影响，并与燃烧法制得的催化剂进行对比，考察了不同催化剂CO2加氢制甲醇的性能。研究表明，延长湿凝胶干燥时间可有效防止催化剂焙烧时发生喷溅，有利于催化剂中各组分的分散，提高催化剂对 H2和 CO2的吸附能力；112℃干燥48 h 制得的催化剂（CZZ-48 h）BET比表面积为43．5 m2／g，高于燃烧法；柠檬酸用量等于化学计量比时催化剂的性能最佳，在240℃、2．6 MPa、空速为3600 h－1、H2／CO2（体积比）为3的条件下甲醇时空收率达109．4 g／（kg· h）；柠檬酸过量会影响催化剂组分的分散度，并造成分解残留覆盖催化剂表面活性位而不利于CO2加氢反应。
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