新型Cu/ZrO_2环己醇脱氢催化剂的制备

Preparation of Cu/ZrO_2 cyclohexanol dehydrogenation catalyst

以硝酸铜、氧氯化锆为原料,配制成n(Zr)∶n(Cu)=(1~4)∶1的溶液,以w(NaOH)=15%溶液为沉淀剂,采用共沉淀法,制备出新型Cu/ZrO2环己醇脱氢催化剂。通过正交试验选择出较优的催化剂制备条件为:n(Zr):n(Cu)=2∶1,锆盐初始浓度0.2mol.L-1,焙烧时间5h,焙烧温度400℃,滴定终点pH值为12。考察了催化剂预处理、反应温度等对脱氢过程产物收率和选择性的影响。在优化条件下制得的催化剂用于环己醇脱氢时,环己酮产品收率达85%,选择性近100%。

Cu/ZrO_2 cyclohexanol dehydrogenation catalyst was prepared by co-precipitation of copper nitrate and zirconium oxychloride solution with n(Zr)n(Cu)=(1-4)1, using 15% sodium hydroxide as the precipitant. Optimum preparation condition was determined by orthogonal experiment as follows: n(Zr)n(Cu)=21,initial concentration of zirconium oxychloride = 0.2 molL^(-1), calcination time 5 h, calcinations temperature 400 , pH at the end of titration = 12. Influence of pretreatment of the catalyst, reaction temperature on the yield and selectivity was investigated. Cyclohexanone yield of 85% and selectivity to cyclohexanone of nearly 100% were attained over the catalyst prepared under optimum condition.