中国炼油与石油化工 ›› 2012, Vol. 14 ›› Issue (3): 59-67.

• Catalyst Research • 上一篇    下一篇

Pd-Ag/Al2O3合金负载型催化剂的反相微乳液法制备、表征及其催化乙炔加氢性能

卫国宾1,戴伟2,李前2,曹维良3,张敬畅4   

  1. 1. 北京化工大学 现代催化研究所
    2. 中国石化北京化工研究院
    3. 北京化工大学
    4. 北京化工大学理学院
  • 收稿日期:2012-03-12 修回日期:2012-05-03 出版日期:2012-09-30 发布日期:2012-10-22
  • 通讯作者: 卫国宾 E-mail:weigb.bjhy@sinopec.com

Reverse microemulsion synthesis and characterization of supported Pd-Ag bimetallic alloy catalysts on Al2O3 for acetylene hydrogenation

  • Received:2012-03-12 Revised:2012-05-03 Online:2012-09-30 Published:2012-10-22

摘要: 采用反相微乳液法合成了Pd-Ag双金属合金纳米粒子,并成功地将其沉积到Al2O3载体表面上制得Pd-Ag合金负载型催化剂。该催化剂应用于乙炔选择加氢反应表现出很好的催化性能。通过UV/Vis、HRTEM、EDX、XRD、XPS等测试手段表征Pd-Ag纳米合金粒子和Pd-Ag/Al2O3催化剂样品,结果表明: 在微乳液中形成的Pd-Ag纳米粒子以合金形态、立方面心结构存在,其粒径分布窄,分散均匀,平均粒径为2nm。微乳液的液滴大小可以有效地限制纳米粒子的长大。TEM照片显示Pd-Ag纳米合金粒子均匀地负载在Al2O3载体上,分散效果良好。考察不同催化剂在碳二馏分选择加氢反应中的催化性能,发现在Pd-Ag纳米合金负载催化剂中Pd:Ag=1:1.5时催化剂性能最佳。

关键词: 反相微乳化, Pd-Ag双金属催化剂, 纳米颗粒, 乙炔加氢

Abstract: Pd-Ag bimetallic alloy nanoparticles were synthesized by the reverse microemulsion method, and then deposited on Al2O3 to form the supported catalyst. The prepared catalysts showed high activity for selective hydrogenation of acety?lene. The nanoparticles of Pd-Ag and Pd-Ag/Al2O3 samples were characterized by the nanoparticle size analyzer, UV/Vis, HRTEM, EDX, XRD, and XPS. The test results indicated that Pd-Ag bimetallic alloy nanoparticles with a size of about 2 nm and a face-centered cubic (fcc) structure were formed in the measured area of microemulsion. The growth of nanopar?ticles was effectively limited within the droplet of micoremulsion. TEM image exhibited that the Pd-Ag alloy nanoparticles were well-dispersed on the Al2O3 support. The catalytic performance of various catalysts during selective hydrogenation of acetylene showed that a higher acetylene conversion and selectivity to ethylene upon acetylene hydrogenation was achieved on a nano-sized Pd-Ag bimetallic catalyst with a Pd/Ag molar ratio of 1:1.5.

Key words: Reverse microemulsion, Pd-Ag bimetallic catalyst, Nanoparticle, Acetylene hydrogenation