化学学报 ›› 2007, Vol. 65 ›› Issue (18): 1933-1939. 上一篇    下一篇

研究论文

多环芳烃在贵金属催化剂上竞争加氢反应的研究

刘会茹1, 徐智策*,2, 赵地顺2   

  1. (1天津大学化工学院催化科学与工程系 天津市应用催化科学与工程重点实验室 天津 300072)
    (2河北科技大学化学与制药工程学院 石家庄 050018)
  • 投稿日期:2007-03-20 修回日期:2007-05-09 发布日期:2007-09-28
  • 通讯作者: 徐智策

Competitive Hydrogenation of Poly-aromatic Hydrocarbons on Supported Noble Metal Catalysts

LIU Hui-Ru1; XU Zhi-Ce*,2; ZHAO Di-Shun2   

  1. (1 Department of Catalysis Science and Technology, School of Chemical Engineering, Tianjin University, Tianjin 300072)
    (2 School of Chemical and Pharmaceutical Engineering, Hebei University of Science and Technology, Shijiazhuang 050018)
  • Received:2007-03-20 Revised:2007-05-09 Published:2007-09-28
  • Contact: XU Zhi-Ce

采用水蒸汽脱铝获得了超稳Y载体, 并用离子交换法制备了金属含量约为0.8 wt%的双贵金属催化剂. 用NH3程序升温脱附、X射线衍射、N2吸附-脱附等方法表征了载体和催化剂. 以萘、蒽、芘加氢为模型反应, 在高压反应釜中研究了催化剂的加氢活性以及它们之间竞争加氢的反应. 结果表明, 催化剂具有深度加氢的能力. 萘与蒽竞争加氢的结果表明, 蒽的加氢活性高于萘加氢活性, 并且蒽抑制萘加氢, 萘抑制了八氢蒽向全氢蒽的转化. 说明对于分子动力学直径相当的混合体系中, 多环物质抑制少环物质的加氢. 分子动力学直径不同的萘与芘加氢结果表明, 萘的转化率始终高于芘的转化率, 并且单和混合体系中萘和芘的转化率变化程度不大, 说明分子能否扩散进入分子筛孔道内也是影响加氢活性的重要因素.

关键词: 贵金属催化剂, 水蒸汽脱铝, 多环芳烃, 竞争加氢

Ultrastable Y support was obtained by steam dealumination. Double noble metal catalyst with a total loading of Pd and Pt 0.8 wt% was prepared by an ion-exchange method. The supports and catalysts were characterized by temperature programmed desorption of ammonia, X-ray diffractograms, and nitrogen adsorption-desorption isotherms. The activity for the hydrogenation of tetralin, anthracene and pyrene was examined with a stirred tank reactor operating at 6.0 MPa and 250 ℃. It was shown that the catalyst promoted deep hydrogenation of polycyclic arenes. Competitive hydrogenation was also examined. For the naphthalene and anthracene, with the same kinetic diameters, hydrogenation activity of the latter was higher than that of the former. In addition, a strong inhibition exists in this reaction system. The results showed that polycyclic arenes inhibited the hydrogenation of arenes with less number of aromatic rings. While for naphthalene and pyrene with different kinetic diameters, the hydrogenation activity of naphthalene was higher than that of pyrene, indicating that another important factor existed besides the number of aromatic rings.

Key words: noble metal catalyst, steam dealumination, polycyclic aromatics, competitive hydrogenation