高等学校化学学报 ›› 2005, Vol. 26 ›› Issue (1): 106.

• 研究论文 • 上一篇    下一篇

Au/ZrO2催化剂中ZrO2的尺寸效应:1,3-丁二烯加氢反应

张鑫, 徐柏庆   

  1. 清华大学化学系, 有机光电子与分子工程教育部重点实验室, 分子催化与定向转化研究室, 北京 100084
  • 收稿日期:2004-02-26 出版日期:2005-01-10 发布日期:2005-01-10
  • 通讯作者: 徐柏庆(1961年出生),男,博士,教授,博士生导师,从事多相催化研究.E-mail:bqxu@mai.ltsinghua.edu.cn E-mail:bqxu@mai.ltsinghua.edu.cn
  • 基金资助:

    国家自然科学基金(批准号:20073023);国家自然科学杰出青年基金(批准号:20125310)资助

Size Effect of Zirconia Nanoparticles in Au/ZrO2 Catalysts for 1,3-Butadiene Hydrogenation

ZHANG Xin, XU Bo-Qing   

  1. Innovative Catalysis Program, Key Lab for Organic Optoelectronics & Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing 100084, China
  • Received:2004-02-26 Online:2005-01-10 Published:2005-01-10

摘要: 在不同温度(673~1073K)下,于流动N2气中焙烧ZrO(OH)2醇(乙醇)凝胶,制备了不同尺寸的ZrO2-AN纳米晶(6~30nm).采用沉积-沉淀方法制备了相应的质量分数为0.7%的Au/ZrO2-AN催化剂.用XRD,XRF,TEM/HRTEM,EDS,N2吸附和1,3-丁二烯加氢反应对ZrO2-AN和Au/ZrO2-AN催化剂进行了表征.结果表明,在所有的Au/ZrO2-AN样品中,Au粒子的平均尺寸为4~5nm,ZrO2-AN的颗粒大小没有因为负载Au粒子而发生改变.1,3-丁二烯在Au/ZrO2-AN催化剂催化下能以100%的选择性进行加氢反应生成单烯烃.随着Au/ZrO2-AN催化剂中ZrO2-AN纳米晶尺寸的增加或“载体”焙烧温度的升高,1,3-丁二烯的转化率明显降低;1-丁烯的选择性先增加后减小,2-丁烯中反/顺异构体的摩尔比在0.5~1.0的范围内逐渐增大,TEM/HRTEM表征结果清楚地表明,Au/ZrO2-AN催化剂中Au粒子与ZrO2-AN颗粒接触界面/周边随ZrO2-AN颗粒尺寸的减小而明显增加,这很可能是含有更小尺寸ZrO2-AN纳米粒子的Au/ZrO2-AN催化剂具有更高的催化活性的重要原因.

关键词: Au/ZrO2催化剂, 1, 3-丁二烯加氢反应, 纳米ZrO2, 尺寸效应, 多相催化

Abstract: This work explores the size-effect of zirconia nano particles on the catalysis of Au/ZrO2-AN catalyst for 1,3-butadiene hydrogenation. Zirconia nanoparticles with different sizes(6—30 nm) were prepared by pretreatment at different temperatures(673—1 073 K) and 0.7%Au/ZrO2-AN-T catalysts by deposition-precipitation method. The samples were characterized with XRD, TEM, XRF and nitrogen adsorption measurements. While the Au particles in all the 0.7%Au/ZrO2-AN-T catalysts appeared to show similar sizes(4—5 nm), the catalytic activity order for 1,3-butadiene hydrogenation clearly revealed that smaller zirconia nanoparticles led to 1%Au/ZrO2-AN-T catalyst with higher catalytic activities. A 100% selectivity to butenes is achieved and the trans to cis ratio in 2-butenes is 0.5—1 over all the 1%Au/ZrO2-AN-T catalysts. The activity improvement by reducing zirconia particle size seems attributable to increased Au-zirconia junctions in the catalyst, as evidenced by the TEM analysis.

Key words: Au/ZrO2 catalyst, 1,3-Butadiene hydrogenation, Zirconia nanoparticles, Size effect, Heterogeneous catalysis

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