物理化学学报 >> 2016, Vol. 32 >> Issue (7): 1765-1774.doi: 10.3866/PKU.WHXB201604085

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Ru/氧化物催化剂在甲苯部分加氢反应中的载体效应

毕慧子1,窦镕飞1,王浩1,裴燕1,乔明华1,*(),孙斌2,宗保宁2,*()   

  1. 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
    2 中国石化石油化工科学研究院,催化材料与反应工程国家重点实验室,北京100083
  • 收稿日期:2016-02-11 发布日期:2016-07-08
  • 通讯作者: 乔明华,宗保宁 E-mail:mhqiao@fudan.edu.cn;zongbn.ripp@sinopec.com
  • 基金资助:
    国家重点基础研究发展规划项目(973)(2012CB224804);国家自然科学基金(21373055);上海市科委科技基金(08DZ2270500);中石化技术开发课题(S411043)

Effect of the Support on Partial Hydrogenation of Toluene over Ru/Oxide Catalysts

Hui-Zi BI1,Rong-Fei DOU1,Hao WANG1,Yan PEI1,Ming-Hua QIAO1,*(),Bin SUN2,Bao-Ning ZONG2,*()   

  1. 1 Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, Fudan University, Shanghai 200433, P. R. China
    2 State Key Laboratory of Catalytic Materials and Reaction Engineering, Research Institute of Petroleum Processing, SINOPEC, Beijing 100083, P. R. China
  • Received:2016-02-11 Published:2016-07-08
  • Contact: Ming-Hua QIAO,Bao-Ning ZONG E-mail:mhqiao@fudan.edu.cn;zongbn.ripp@sinopec.com
  • Supported by:
    the National Key Basic Research Program of China (973)(2012CB224804);National Natural Science Foundation of China(21373055);Science and Technology Commission of Shanghai Municipality, China(08DZ2270500);Technology Development Programof SINOPEC, China(S411043)

摘要:

采用浸渍-化学还原法制备了一系列负载型Ru催化剂,考察了一些常见的氧化物载体(SiO2m-ZrO2t-ZrO2γ-Al2O3和P25)对甲苯部分加氢制甲基环己烯催化性能的影响。采用N2物理吸附、X射线粉末衍射(XRD)、透射电子显微镜(TEM)和X射线光电子能谱(XPS)等手段对催化剂进行了系统的表征。研究表明,载体通过影响Ru的粒径,进而影响甲苯部分加氢催化性能。当Ru纳米粒子的粒径由2.6 nm增大到17.3 nm时,甲苯的转换频率(TOF)以及甲基环己烯初始选择性(S0)先增加,然后降低,呈火山型变化趋势,二者的最大值均在Ru粒径为3.0 nm时出现。在催化性能最优的Ru/P25催化剂上,进一步考察了修饰剂的种类和浓度、反应温度、反应压力等条件的影响。当反应温度为423 K、H2压力为5.0 MPa,以0.25 g七水合硫酸锌为修饰剂时,Ru/P25催化剂上的初始加氢速率(r0)为26 mmol·g-1·min-1S0为57%,甲基环己烯得率可达36%。

关键词: 载体, 钌, 甲苯, 部分加氢, 甲基环己烯

Abstract:

The supported Ru catalysts were prepared by the impregnation-chemical reduction method to investigate the effect of some conventional oxide supports (SiO2, m-ZrO2, t-ZrO2, γ-Al2O3, and P25) on the partial hydrogenation of toluene to methylcyclohexenes. The catalysts were characterized by N2 physisorption, powder X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). It was found that the supports influenced the size of the Ru nanoparticles (NPs) and consequently the catalytic performance. With the increase in the size of the Ru NPs from 2.6 to 17.3 nm, the turnover frequency (TOF) of toluene and the initial selectivity (S0) to methylcyclohexenes increased first, reached the maximum, and then decreased, following a volcano-like curve. At the Ru particle size of 3.0 nm, both TOF and S0 reached the highest values. Reaction conditions, such as the type and concentration of the modifiers, the temperature, and the pressure, were optimized over the best Ru/P25 catalyst among the supported Ru catalysts investigated herein. Under the reaction conditions of 423 K, H2 pressure of 5.0 MPa, and using 0.25 g zinc sulfate heptahydrate as the modifier, the initial hydrogenation activity (r0) of 26 mmol·g-1·min-1, the S0 of 57%, and the methylcyclohexenes yield of 36% were obtained.

Key words: Support, Ruthenium, Toluene, Partial hydrogenation, Methylcyclohexene