石油学报（石油加工）
石油學報（石油加工）
석유학보（석유가공）
ACTA PETROLEI SINICA(PETROLEUM PROCESSING SECTION)
2009年
6期
868-872
,共5页
钯%氧化铝%过氧化氢异丙苯%二甲基苄醇%催化加氢
鈀%氧化鋁%過氧化氫異丙苯%二甲基芐醇%催化加氫
파%양화려%과양화경이병분%이갑기변순%최화가경
Pd%A1+2O_3%cumene hydroperoxide%a-cumyl alcohol%catalytic hydrogenation
分别以K_2[PdCl_4]和K_2[PdCl_4]与草酸的混合液为Pd前驱体,采用浸渍沉淀法制备了Pd/A1_2O_3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/A1_2O_3催化剂进行了表征.考察了Pd/AI_2O_3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A1_2O_3上呈不均匀分布,并发生团聚,其颗粒直径为5～10 nm;催化剂在煅烧及还原过程中,活性金属Pd与载体Al_2O_3发生强烈相互作用,产生了Pd-Al合金.以K_2[PdCl_4]为前驱体制备的Pd/A1_2O_3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240 h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.
分彆以K_2[PdCl_4]和K_2[PdCl_4]與草痠的混閤液為Pd前驅體,採用浸漬沉澱法製備瞭Pd/A1_2O_3催化劑.採用等離子體耦閤髮射原子吸收光譜(ICP-AES)、透射電鏡(TEM)、程序升溫還原(TPR)等手段對Pd/A1_2O_3催化劑進行瞭錶徵.攷察瞭Pd/AI_2O_3催化劑在過氧化氫異丙苯(CHP)固定床加氫反應中的催化活性.結果錶明,金屬Pd在載體A1_2O_3上呈不均勻分佈,併髮生糰聚,其顆粒直徑為5～10 nm;催化劑在煅燒及還原過程中,活性金屬Pd與載體Al_2O_3髮生彊烈相互作用,產生瞭Pd-Al閤金.以K_2[PdCl_4]為前驅體製備的Pd/A1_2O_3催化劑在過氧化氫異丙苯(CHP)固定床加氫反應中顯示瞭較高的二甲基芐醇(CA)選擇性,而且在240 h連續反應過程中,CHP 的轉化率始終維持在100%,目標產物CA的平均選擇性也達到瞭97.7%.通過對比反應前後反應體繫的組成,探討瞭CHP液相催化加氫製備CA的反應途徑.
분별이K_2[PdCl_4]화K_2[PdCl_4]여초산적혼합액위Pd전구체,채용침지침정법제비료Pd/A1_2O_3최화제.채용등리자체우합발사원자흡수광보(ICP-AES)、투사전경(TEM)、정서승온환원(TPR)등수단대Pd/A1_2O_3최화제진행료표정.고찰료Pd/AI_2O_3최화제재과양화경이병분(CHP)고정상가경반응중적최화활성.결과표명,금속Pd재재체A1_2O_3상정불균균분포,병발생단취,기과립직경위5～10 nm;최화제재단소급환원과정중,활성금속Pd여재체Al_2O_3발생강렬상호작용,산생료Pd-Al합금.이K_2[PdCl_4]위전구체제비적Pd/A1_2O_3최화제재과양화경이병분(CHP)고정상가경반응중현시료교고적이갑기변순(CA)선택성,이차재240 h련속반응과정중,CHP 적전화솔시종유지재100%,목표산물CA적평균선택성야체도료97.7%.통과대비반응전후반응체계적조성,탐토료CHP액상최화가경제비CA적반응도경.
Two Pd/Al_2O_3 catalysts were synthesized by using K_2[PdCl_4] and a mixture of K_2[PdCl_4] 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-Al alloy was formed in the treatments of calcinations and reduction due to the strong interaction between Pd and Al_2O_3.The CHP conversion of 100% and the mean CA selectivity of 97.7% were obtained, respectively, in 240 h CHP hydrogenation over Pd/Al_2O_3 prepared from K_2[PdCl_4].Meanwhile, reaction pathways of catalytic hydrogenation of CHP in cumene solution over Pd/Al_2O_3 were also discussed on the basic of analyzing and comparing the compositions of the system before and after reaction.
