Pd/Al_2O_3催化过氧化氢异丙苯的液相加氢反应  

CATALYTIC HYDROGENATION OF CUMENE HYDROPEROXIDE OVER Pd/Al_2O_3 CATALYST

作　　者：朱庆才[1] 沈本贤[1] 

机构地区：[1]华东理工大学化学工程联合国家重点实验室石油加工研究所,上海200237

出　　处：《石油学报（石油加工）》2009年第6期868-872,共5页Acta Petrolei Sinica(Petroleum Processing Section)

摘　　要：分别以K2[PdCl4]和K2[PdCl4]与草酸的混合液为Pd前驱体,采用浸渍沉淀法制备了Pd/Al2O3催化剂。采用等离子体耦合发射原子吸收光谱(ICP-AES)、透射电镜(TEM)、程序升温还原(TPR)等手段对Pd/Al2O3催化剂进行了表征。考察了Pd/Al2O3催化剂在过氧化氢异丙苯(CHP)固定床加氢反应中的催化活性。结果表明,金属Pd在载体Al2O3上呈不均匀分布,并发生团聚,其颗粒直径为5～10nm;催化剂在煅烧及还原过程中,活性金属Pd与载体Al2O3发生强烈相互作用,产生了Pd-Al合金。以K2[PdCl4]为前驱体制备的Pd/Al2O3催化剂在过氧化氢异丙苯(CHP)固定床加氢反应中显示了较高的二甲基苄醇(CA)选择性,而且在240h连续反应过程中,CHP的转化率始终维持在100%,目标产物CA的平均选择性也达到了97.7%。通过对比反应前后反应体系的组成,探讨了CHP液相催化加氢制备CA的反应途径。Two Pd/Al2O3 catalysts were synthesized by using K2[PdCl4] and a mixture of K2 [PdCl4] and oxalic acid as precursors, respectively. The samples were characterized by means of inductively coupled plasma atomic emission spectroscopy （ICP-AES）, transmission electron microscopy （TEM） and temperature-programmed reduction （TPR）. The catalytic activities of the samples were tested in the transformation of a cumyl alcohol （CA） from cumene hydroperoxide （CHP） in cumene solution with hydrogen as a reducing agent in a fixed bed reactor. The results showed that the Pd particles loading on the alumina were misdistribution and agglomeration with a mean particle diameter of about 5- 10 nm, and Pd A1 alloy was formed in the treatments of calcinations and reduction due to the strong interaction between Pd and Al2O3. The CHP conversion of 100% and the mean CA selectivity of 97.7% were obtained, respectively, in 240 h CHP hydrogenation over Pd/Al2O3 prepared from K2[PdCl4]. Meanwhile, reaction pathways of catalytic hydrogenation of CHP in cumene solution over Pd/Al2O3 were also discussed on the basic of analyzing and comparing the compositions of the system before and after reaction.

关 键 词：钯 氧化铝 过氧化氢异丙苯 二甲基苄醇 催化加氢 

分 类 号：TQ203.2[化学工程—有机化工]