催化学报

催化学报 ›› 2012, Vol. 33 ›› Issue (6): 1055-1060.DOI: 10.3724/SP.J.1088.2012.11142

• 研究论文 • 上一篇    下一篇

ZnO 或 K2O 助剂对 Cu/SiO2-Al2O3 催化剂上丙三醇和苯胺气相催化合成 3-甲基吲哚反应的促进作用

张跃, 孙薇, 石雷*, 孙琪   

  1. 辽宁师范大学功能材料化学研究所, 辽宁大连 116029
  • 收稿日期:2011-12-27 修回日期:2012-03-15 出版日期:2012-05-30 发布日期:2012-05-30

Promoting Effect of ZnO or K2O on Cu/SiO2-Al2O3 Catalyst for Vapor-Phase Synthesis of 3-Methylindole from Glycerol and Aniline

ZHANG Yue, SUN Wei, SHI Lei*, SUN Qi   

  1. Institute of Chemistry for Functionalized Materials, Liaoning Normal University, Dalian 116029, Liaoning, China
  • Received:2011-12-27 Revised:2012-03-15 Online:2012-05-30 Published:2012-05-30

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摘要： 研究了 ZnO 或 K2O 助剂对 Cu/SiO2-Al2O3 上丙三醇和苯胺气相催化合成 3-甲基吲哚反应的促进作用, 采用 X 射线衍射、透射电子显微镜、H2 程序升温还原、NH3 程序升温脱附以及热重-差热分析等技术对催化剂进行了表征. 结果表明, 适量 ZnO 或 K2O 的加入可明显提高催化剂的活性、选择性和稳定性, 其中以 ZnO 的促进作用更强. ZnO 不仅能增强活性组分 Cu 与 SiO2-Al2O3 载体之间的相互作用、提高 Cu 在载体表面的分散度, 而且可有效抑制反应过程中 Cu 粒子的烧结; 而 K2O 的加入却降低了 Cu 分散度, 但也对反应过程中 Cu 粒子的烧结有所抑制. ZnO 或 K2O 的加入均不同程度地增加了 Cu/SiO2-Al2O3 催化剂的弱酸中心数量, 从而促进 3-甲基吲哚的生成.

关键词: 铜, 二氧化硅, 氧化铝, 氧化锌, 氧化钾, 3-甲基吲哚, 丙三醇, 苯胺

Abstract: The promoting effect of ZnO or K2O promoter on Cu/SiO2-Al2O3 catalyst for the vapor-phase synthesis of 3-methylindole from glycerol and aniline was studied. The catalyst samples were characterized by X-ray diffraction, transmission electron microscopy, H2 temperature-programmed reduction, NH3 temperature-programmed desorption, and thermogravimetric and differential thermal analysis. The results indicated that the addition of an appropriate amount ZnO or K2O to Cu/SiO2-Al2O3 increased the activity and selectivity as well as the stability of the catalyst remarkably, and ZnO exhibited better efficiency than K2O. ZnO not only reinforced the interaction between the active component and the support, promoted the dispersion of copper particles on the support, but also inhibited the sintering of copper particles during the reaction. K2O could suppress the sintering of copper particles during the reaction to some extent although it did not improve the dispersion of copper particles on the support. The addition of ZnO or K2O to Cu/SiO2-Al2O3 increased the number of weak acid sites in different degrees, which promoted the synthesis of 3-methylindole.

Key words: copper, silica, alumina, zinc oxide, potassium oxide, 3-methylindole, glycerol, aniline