论文部分内容阅读
螯合辅助溶剂挥发共组装法制备的炭-氧化铝复合材料为载体,分别使用水、乙醇或二者混合物为氯铂酸的分散介质,浸渍制备炭-氧化铝复合材料负载Pt催化剂.通过XRD,N2物理吸附以及TEM表征可知,乙醇作为浸渍溶剂时,最有利于Pt的分散,而混合溶剂浸渍制备的催化剂Pt颗粒最大.2-氧-4-苯基丁酸乙酯不对称加氢反应结果表明,氯铂酸水溶液浸渍得到的催化剂Pt纳米粒子的粒径有利于获得高的光学选择性,催化剂经辛可尼丁修饰后,以乙酸为反应溶剂,可获得最高84.8%的光学选择性.此外,该催化剂重复利用性能优异,可以重复利用22次,活性没有下降.
Chelating auxiliary solvent evaporation co-assembled carbon-alumina composite prepared by the carrier as a carrier, respectively, the use of water, ethanol or a mixture of both chloroplatinic acid dispersion medium, impregnated prepared carbon-alumina composite supported Pt catalyst by XRD , N2 physisorption and TEM characterization, it is found that ethanol is most favorable for the dispersion of Pt when impregnated with ethanol, while the Pt particles prepared by impregnation with mixed solvents are the largest.2 Asymmetric hydrogenation of ethyl 2-oxo- 4-phenylbutyrate The results show that the particle size of the catalyst Pt nanoparticles impregnated with aqueous solution of chloroplatinic acid is conducive to obtaining high optical selectivity. After the catalyst is modified with cinchonidine, the optical selectivity of up to 84.8% can be obtained with acetic acid as the reaction solvent In addition, the catalyst has excellent reusability and can be reused for 22 times with no decrease in activity.