催化学报

催化学报 ›› 2010, Vol. 31 ›› Issue (8): 987-992.DOI: 10.1016/S1872-2067(10)60098-8

• 研究论文 • 上一篇    下一篇

甲醇脱水合成二甲醚的 Al2O3-HZSM-5 组合固体酸催化剂

张立伟, 王军华, 吴佩, 侯昭胤, 费金华, 郑小明   

  1. 浙江大学化学系, 浙江杭州 310028
  • 收稿日期:2010-04-06 出版日期:2010-08-30 发布日期:2013-12-26

Synthesis of Dimethyl Ether via Methanol Dehydration over Combined Al2O3-HZSM-5 Solid Acids

ZHANG Liwei, WANG Junhua, WU Pei, HOU Zhaoyin, FEI Jinhua*, ZHENG Xiaoming   

  1. Institute of Catalysis, Department of Chemistry, Key Laboratory of Applied Chemistry of Zhejiang Province, Zhejiang University, Hangzhou 310028, Zhejiang, China
  • Received:2010-04-06 Online:2010-08-30 Published:2013-12-26

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1423

被引次数

9

摘要： 制备了可用于固定床反应器中甲醇脱水制备二甲醚的 Al2O3-HZSM-5 组合固体酸催化剂系列, 并采用 X射线衍射、扫描电镜、N2 物理吸附和氨气程序升温脱附等对其进行了表征. 结果表明, 在浸渍法制备的组合 Al2O3-HZSM-5 催化剂中, 细小的氧化铝颗粒高度分散在 HZSM-5 分子筛的周围; 在化学沉淀法制备的组合 Al2O3-HZSM-5 催化剂中, 一层氧化铝膜覆盖在 HZSM-5 分子筛的颗粒外层. 所制备的催化剂都具有较多的大孔和介孔比表面积, 在低温 (235 oC) 和高空速 (30 h–1) 条件下具有较高的甲醇脱水反应活性和稳定性, 其中在化学沉淀法制备的组合 Al2O3-HZSM-5 催化剂上, 二甲醚产率达到 13.5 g/(g•h).

关键词: 组合固体酸, 氧化铝, HZSM-5, 甲醇, 二甲醚

Abstract: Combined Al2O3-HZSM-5 solid acids were prepared and used for methanol dehydration to dimethyl ether (DME) in a fixed-bed reactor. The physicochemical properties of the combined solid acids were characterized by X-ray diffraction, field emission scanning electron microscopy, N2 adsorption, and NH3 temperature-programmed desorption. Al2O3 was highly dispersed in Al2O3-HZSM-5 after impregnation (Al2O3-HZSM-5-IM), while a layered Al2O3-covered HZSM-5 structure solid acid was synthesized via chemical precipitation (Al2O3-HZSM-5-CP). Both the combined Al2O3-HZSM-5 solid acids prepared by impregnation and chemical precipitation have a higher surface area and more meso- and macropores. The combined Al2O3-HZSM-5 solid acids exhibit higher methanol dehydration activity than pure Al2O3 and it possesses higher stability than pure HZSM-5 at a lower temperature (235 ?C) and a higher LHSV (30 h?1). The stable DME productivities for Al2O3-HZSM-5-IM and Al2O3-HZSM-5-CP at 235 ?C reached 12.7 and 13.5 g/(g•h), respectively.

Key words: combined solid acid, alumina, HZSM-5, methanol, dimethyl ether