Cu/SiO_2催化剂的制备及对羟基苯乙酸乙酯加氢催化性能

The preparation of Cu/SiO_2 catalysts and its catalytic property on ethyl p-hydroxyphenylacetate hydrogenation

分别采用浸渍法、沉积沉淀法和共沉淀法制备了Cu/SiO_2催化剂,利用低温N2物理吸附、XRD、H2-TPR等手段对其进行表征,并研究了该催化剂催化对羟基苯乙酸乙酯加氢的性能。结果表明,制备方法对Cu/SiO_2催化剂中Cu物种分散行为及还原性能有较大影响,进而使催化剂表现出不同的加氢活性。采用共沉淀法制备的Cu/SiO_2催化剂,活性物种Cu物种高度分散,且易于还原,表现出最佳的加氢活性,在催化剂用量为m(对羟基苯乙酸乙酯)∶m(催化剂)=25∶2.5,反应温度170℃,反应压力4MPa,反应时间15h条件下,对羟基苯乙醇收率达到99.2%。

Cu/SiO_2 catalysts were prepared by impregnation,deposition precipitation and co-precipitation methods.The obtained catalysts were characterized by N_2 physisorption,XRD and H_2-TPR,also the catalytic property were studied in the hydrogenation of ethyl p-hydroxyphenylacetate to produce p-hydroxyphenylethyl alcohol.It was found that the catalysts showed obvious differences in hydrogenation performance,due to the different reduction property and dispersion of Cu species among the catalysts prepared by different methods.The Cu/SiO_2 catalyst prepared by co-precipitation method had better reduction property and higher CuO dispersion,and showed the highest yield（99.2%）of p-hydroxyphenethyl alcohol under hydrogenation conditions：catalyst amount 2.5g,reaction temperature 170℃,reaction pressure 4MPa,reaction time 15 h.