过氧化氢异丙苯催化加氢法制备二甲基苄醇

Preparation Dimethylphenyl-Carbinol by Catalytic Hydrogenation of Cumene Hydroperoxide

采用浸渍法制备了负载Pd和Pt的HPC-1催化剂,并用X射线衍射和扫描电子显微镜等手段对催化剂进行了表征;同时分别在间歇式反应釜和固定床连续反应器中对过氧化氢异丙苯(CHP)催化加氢制备二甲基苄醇(DMPC)的反应活性进行了评价。实验结果表明,HPC-1催化剂中活性金属Pd和Pt以无定形非晶态形式负载于载体上;在优化的反应工艺(反应温度68℃、反应压力0.5MPa、液态空速2.0h-1、氢气流量150mL/min)条件下,无论是在间歇式反应釜内还是在固定床反应器内,CHP的转化率均大于99%,DMPC的选择性均大于97%,达到了现有硫化碱还原CHP制备DMPC工艺的水平;建立了反应温度为68℃时CHP在固定床反应器内进行催化加氢反应的宏观反应动力学模型,运用非线性最小二乘法计算得到该模型的反应级数为0.79,且CHP含量的计算值与实验值相吻合。

A Pd and Pt supported catalyst, HPC-1, was prepared by impregnation and characterized by means of XRD and SEM. The Pd and Pt supported on support are in amorphous state. The catalyst activity in hydrogenation of cumene hydroperoxide （CLIP） to dimethylphenyl carbinol （DMPC） was evaluated in both stirred tank reactor and fixed-bed reactor separately. Under the optimized reaction conditions： 68 ℃, 0.5 MPa, LHSV 2.0 h^-1 and H2 flow rate 150 mL/min, the conversion of CHP is above 99% and selectivity to DMPC is above 97% for either reactor. The results are similar to preparation process of DMPC from CHP by reduction of basic sulfide. Kinetics model of CHP hydrogenation on HPC-1 catalyst at 68 ℃ in a fixed-bed reactor is established and its parameters are obtained from experimental data by using nonlinear least square method. The reaction order is 0.79 and the concentration of CHP calculated from the model agrees with experimental data.