物理化学学报 >> 2010, Vol. 26 >> Issue (02): 378-384.doi: 10.3866/PKU.WHXB20100232

催化和表面结构 上一篇    下一篇

纳米晶簇多级孔道L沸石的合成及其脱硫性能

霍全, 窦涛, 巩雁军, 赵震, 邓风, 喻志武, 潘惠芳   

  1. 中国石油大学(北京)CNPC催化重点实验室, 北京 102249; 中国科学院武汉物理与数学研究所, 武汉 430071
  • 收稿日期:2009-08-26 修回日期:2009-11-02 发布日期:2010-01-26
  • 通讯作者: 窦涛 E-mail:doutao@cup.edu.cn

Synthesis and Desulfurization Performance of Nanocrystal-Assembled Zeolite L with a Hierarchical Pore Structure

HUO Quan, DOU Tao, GONG Yan-Jun, ZHAO Zhen, DENG Feng, YU Zhi-Wu, PAN Hui-Fang   

  1. Key Laboratory of Catalysis, China National Petroleum Corporation, China University of Petroleum, Beijing 102249, P. R. China; Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, P. R. China
  • Received:2009-08-26 Revised:2009-11-02 Published:2010-01-26
  • Contact: DOU Tao E-mail:doutao@cup.edu.cn

摘要:

采用晶化培育法制备了L沸石纳米晶簇, 以其作为前驱体, 并以3-三甲基甲硅烷基丙基十六烷基二甲基氯化铵(TPHAC)为模板剂, 合成了微孔-介孔多级孔道L沸石(MeLTL沸石). 通过X射线衍射(XRD)、氮气吸附-脱附、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、27Al固体魔角核磁(27Al MAS NMR)和吡啶傅立叶变换红外(Py-FTIR)等方法对MeLTL沸石进行了表征. 研究结果表明, MeLTL沸石是由L沸石纳米晶簇自组装形成的, 并具有介孔孔道和L沸石的微孔结构以及适宜的酸量与酸强度, 其比表面积和孔体积分别高达611 m2·g-1和0.696 cm3·g-1. 将MeLTL沸石作为添加剂引入柴油加氢脱硫催化剂载体中, 并与添加L沸石、Al-MCM-41和仅以γ-Al2O3为载体的催化剂进行比较, 其脱硫性能为最佳, 经加氢后的柴油硫含量仅为9.3 μg·g-1, 脱硫率达99.3%.

关键词: 加氢脱硫, L沸石, 介微孔复合孔道, TPHAC, 柴油, 加氢催化剂

Abstract:

Zeolite MeLTL with a micro-mesoporous composite pore structure was synthesized by using nanocrystal clusters of zeolite L prepared by the crystallization nurturing method as a precursor and [3-(trimethoxysilyl)propyl] hexadecyldimethylammonium chloride (TPHAC) as the organic mesopore directing surfactant. Several techniques including X-ray diffraction (XRD), nitrogen adsorption-desorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), 27Al magic angle spinning nuclear magnetic resonance (27Al MAS NMR), and Fourier transform infrared spectroscopy of pyridine adsorption (Py-FTIR) were used to characterize the samples. Results show that zeolite MeLTL is formed by the self-assembly of zeolite L nanocrystals, and it has bimodal pore distributions with a stepwise mesoporous structure and the microporous structure of zeolite L. The BET surface area and the pore volume increased significantly and were 611 m2·g-1 and 0.696 cm3·g-1, respectively. Zeolite MeLTL was composed of zeolite L units and this was responsible for the adequate surface acid amount and acid strength. As a result, the pore diffusion ability and the catalytic performance of zeolite MeLTL are enhanced by the improvement in textural properties. For diesel hydrodesulfurization, the catalyst introduced zeolite MeLTL gave better hydrodesulfurization activity compared to the catalysts introduced zeolite L or Al-MCM-41 or used bare γ-Al2O3 as a support. The sulfur content of diesel oil after hydrotreatment was 9.3 μg·g-1 and the desulfurization rate was 99.3%.

Key words: Hydrodesulfurization, Zeolite L, Micro-mesoporous composite structure, TPHAC, Diesel oil, Hydrogenation catalyst

MSC2000: 

  • O647