化学学报 ›› 2012, Vol. 70 ›› Issue (03): 325-330.DOI: 10.6023/A1110121 上一篇    下一篇

研究论文

添加聚乙二醇对CuZnAl 浆状催化剂结构和性能的影响

高志华, 贾钦, 程凯, 阴丽华, 黄伟   

  1. 太原理工大学煤科学与技术教育部和山西省重点实验室 太原 030024
  • 投稿日期:2011-10-12 修回日期:2011-12-06 发布日期:2011-12-19
  • 通讯作者: 黄伟 E-mail:huangwei@tyut.edu.cn
  • 基金资助:

    国家自然科学基金(No. 20706039)、2010 年山西省高等学校优秀青年学术带头人支持计划和973 计划(No. 2012CB723105)资助项目.

Effect of Polyethylene Glycol on Structure and Performance of CuZnAl Slurry Catalyst

Gao Zhihua, Jia Qin, Cheng Kai, Yin Lihua, Huang Wei   

  1. Key Laboratory of Coal Science and Technology of Ministry of Education and Shanxi Province, Taiyuan University of Technology, Taiyuan 030024
  • Received:2011-10-12 Revised:2011-12-06 Published:2011-12-19
  • Supported by:

    Project was supported by the National Natural Science Foundation of China (No. 20706039), the Program for the Top Young Academic Leaders of Higher Learning Institutions of Shanxi of China in 2010 and the National Basic Research Program of China (No. 2012CB723105).

首先利用共沉淀沉积法制备CuZnAl 催化剂前驱体, 并且通过添加聚乙二醇(PEG600)对其进行改性, 最后采用完全液相法对前驱体进行热处理制得浆状催化剂, 考察了其在浆态床合成气一步法制二甲醚反应中的催化性能, 采用X 射线粉末衍射、程序升温还原、氨程序升温脱附和X 射线光电子能谱对其进行了表征. 结果表明, PEG600 的添加促进了催化剂中铜组分在热处理过程中被还原成低价铜, 提高了催化剂中Cu2O的分散性, 改变了催化剂表面酸量和酸强度的分布, 同时PEG600 的添加方式对催化剂的甲醇合成和甲醇脱水能力有显著影响. 在硝酸铜和硝酸锌水溶液中添加0.5 wt%的PEG600 时, 在热处理过程中形成的Cu2O 最稳定, 不易被还原, 其晶粒度小, 进而使CO 转化率大幅度提高.

关键词: 聚乙二醇, 共沉淀沉积法, 完全液相法, CuZnAl 浆状催化剂, 二甲醚

CuZnAl precursor was prepared by coprecipitation sedimentation method and modified by addition of polyethylene glycol (PEG600). Slurry catalyst was then obtained by heat-treatment using complete- liquid phase technology. The performance of the catalysts for the direct synthesis of dimethyl ether from syngas was evaluated in a slurry reactor. Characterization of the catalysts was carried out by powder X-ray diffraction, H2 temperature-programmed reduction, temperature-programmed desorption of ammonia and X-ray photoelectron spectrometry. The results indicated that PEG600 could effectively promote the reduction of the copper species in catalysts and improve the Cu2O dispersion. The amount of acid and the acidic distribution of catalyst were also changed due to addition of PEG600. Moreover, marked influences were found on methanol synthesis and dehydration capability when PEG600 was added in different way. A significant increase of activity was achieved when the catalyst was prepared in the condition of adding 0.5 wt% PEG600 into the solution of copper nitrate and zinc nitrate. This was attributed to the stable Cu2O with small grain size formed during the heat-treatment process.

Key words: polyethylene glycol, coprecipitation sedimentation method, complete liquid-phase technology, CuZnAl slurry catalyst, dimethyl ether