催化学报

催化学报 ›› 2013, Vol. 34 ›› Issue (5): 898-905.DOI: 10.1016/S1872-2067(12)60540-3

• 研究论文 • 上一篇    下一篇

制备方法对Al2O3掺杂Pt/WO3-ZrO2催化剂上正庚烷异构化反应的影响

尚书宁, 徐欣, 谢鹏飞, 乐英红, 华伟明, 高滋   

  1. 复旦大学化学系, 上海市分子催化和功能材料重点实验室, 上海 200433
  • 收稿日期:2012-12-31 修回日期:2013-05-20 出版日期:2013-05-06 发布日期:2013-05-06
  • 通讯作者: 华伟明,高滋
  • 基金资助:

    国家自然科学基金(20633030,20773027,21273043);高等学校博士学科点专项科研基金(20100071110008);上海市科学技术委员会项目(08DZ2270500).

Influence of preparative method on Al2O3-doped Pt/WO3-ZrO2 catalyst for n-heptane isomerization

SHANG Shuning, XU Xin, XIE Pengfei, YUE Yinghong, HUA Weiming, GAO Zi   

  1. Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, Fudan University, Shanghai 200433, China
  • Received:2012-12-31 Revised:2013-05-20 Online:2013-05-06 Published:2013-05-06
  • Supported by:

    This work was supported by the National Natural Science Foundation of China (20633030, 20773027, 21273043), the Research Fund for the Doctoral Program of Higher Education (20100071110008), and the Science and Technology Commission of Shanghai Municipality (08DZ2270500).

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摘要：

采用恒pH法和非恒pH法制备了Al2O3掺杂的Pt/WO3/ZrO2催化剂,并用N2吸附-脱附、X射线衍射、紫外-可见漫反射、CO化学吸附、X射线光电子能谱、27Al魔角旋转核磁共振和吡啶吸附红外等技术对催化剂进行了表征.结果表明,相比于非恒pH法制备的催化剂,恒pH法制备的催化剂具有较高的比表面积和Pt分散度,在H2气氛中产生更多的B酸位,从而表现出更高的催化正庚烷临氢异构化反应活性; 在200℃和质量空速0.9h-1的反应条件下,正庚烷转化率达70.0%,明显高于非恒pH法制备的催化剂(43.5%).

关键词: 铂, 氧化钨, 氧化锆, 氧化铝掺杂, 制备方法, 正庚烷临氢异构化, 质子酸位

Abstract:

Alumina-doped Pt/WO3/ZrO2 catalysts were prepared using either a constant or variable pH method. The obtained catalyst samples were characterized using N2 adsorption, X-ray diffraction, ultraviolet-visible diffuse reflectance, CO chemisorption, X-ray photoelectron spectroscopy, 27Al magic-angle spinning nuclear magnetic resonance, and infrared spectroscopy of adsorbed pyridine. Compared to the catalyst prepared using the variable pH method, the catalyst prepared using the constant pH method had a higher surface area and Pt dispersion. More Brönsted acid sites were generated in the presence of H2 on the latter catalyst, and this was responsible for its higher catalytic activity in n-heptane hydroisomerization. When the reaction temperature was 200℃ and the weight hourly space velocity of n-heptane was 0.9 h-1, the Pt/WO3/Al2O3-ZrO2 catalyst prepared using the constant pH method gave 70.0% conversion of n-heptane, which was significantly greater than the conversion obtained using the corresponding catalyst prepared using the variable pH method (43.5%).

Key words: Platinum, Tungsten oxide, Zirconia, Alumina doping, Preparative method, n-Heptane hydroisomerization, Protonic acid sites