固体强酸催化剂Pd/WO_3-ZrO_2的制备及其对正庚烷异构化反应的催化性能  

Preparation of Pd/WO_3-ZrO_2 Solid Superacid Catalyst and Its Catalytic Performance for n-Heptane Hydroisomerization

作　　者：徐平[1] 徐云鹏[1] 滕飞[2] 胡胜[3] 谭明伟[3] 徐竹生[1] 田志坚[1] 

机构地区：[1]中国科学院大连化学物理研究所天然气化工与应用催化研究室,辽宁大连116023 [2]国科学院大连化学物理研究所天然气化工与应用催化研究室,辽宁大连116023 [3]大庆石化公司研究院,黑龙江大庆163714

出　　处：《催化学报》2005年第9期750-754,共5页

基　　金：中国科学院知识创新工程领域前沿项目(DICPK2003D4).

摘　　要：采用共沉淀方法制备了固体酸载体WO3-ZrO2,考察了W含量和焙烧温度等对WO3-ZrO2酸性和物相结构的影响,并且考察了Pd/WO3-ZrO2催化剂对正庚烷异构化反应的催化性能. 结果表明,Pd/WO3-ZrO2催化剂的催化性能与固体强酸的W含量及晶相结构密切相关. 在w(W)=13.2%～15.8%时,经700～800 ℃焙烧,WO3在ZrO2表面达到单层分散,且大部分ZrO2以四方晶相存在,所制备的0.5%Pd/WO3-ZrO2对正庚烷异构化反应的催化活性可达到70.4%,选择性可达到81.0%.The WO3-ZrO2 support was synthesized by the coprecipitation method, and the Pd/WO3-ZrO2 solid superacid catalyst was prepared by impregnation. The physicochemical properties of the support and the catalyst were characterized by means of N2 adsorption, XRD, NH3-TPD and He-adsorption. The structure, acid density and activity of the Pd/WO3-ZrO2 catalyst varicd with the W content. The catalytic performance of Pd/WO3-ZrO2 for hydroisomerization of n-heptane was investigated under the reaction conditions of ,n （H2）/n （n-C7H16） = 28, WHSV=0.75 h^-1 V（cat） =0.5 ml, p = 100 kPa and θ=150-410℃ . The Pd/WO3-ZrO2 catalyst sample with w（w） = 13.2% - 15.8% exhibited better performance （ X（n-C7H16） = 70.4% , S（ i-CyH16） = 81.0% ） at 230 ℃. The W content, Pd loading and calcination temperature were essential to obtain the catalyst with high catalytic activity.

关 键 词：钯 氧化钨 氧化锆 负载型催化剂 庚烷 加氢异构化 

分 类 号：O643.36[理学—物理化学]