物理化学学报 >> 2011, Vol. 27 >> Issue (11): 2651-2658.doi: 10.3866/PKU.WHXB20111018

催化和表面科学 上一篇    下一篇

CuO-TiO2-ZrO2/HZSM-5催化CO2加氢制二甲醚

王嵩, 毛东森, 郭晓明, 卢冠忠   

  1. 上海应用技术学院化学与环境工程学院, 应用催化研究所, 上海 200235
  • 收稿日期:2011-05-09 修回日期:2011-07-18 发布日期:2011-10-27
  • 通讯作者: 毛东森 E-mail:dsmao@sit.edu.cn
  • 基金资助:

    上海市科委(08520513600), 上海市教委重点学科(J51503)和上海市优秀青年教师专项基金(yyy10078)资助项目

Dimethyl Ether Synthesis from CO2 Hydrogenation over CuO-TiO2-ZrO2/HZSM-5 Catalysts

WANG Song, MAO Dong-Sen, GUO Xiao-Ming, LU Guan-Zhong   

  1. Research Institute of Applied Catalysis, School of Chemical and Environmental Engineering, Shanghai Institute of Technology, Shanghai 200235, P. R. China
  • Received:2011-05-09 Revised:2011-07-18 Published:2011-10-27
  • Contact: MAO Dong-Sen E-mail:dsmao@sit.edu.cn
  • Supported by:

    The project was supported by the Science and Technology Commission of Shanghai Municipality, China (08520513600), Leading Academic Discipline Project of Shanghai Education Committee, China (J51503) and Shanghai Special Fund for Outstanding Young Teachers, China (yyy10078).

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摘要： 采用共沉淀法制备了一系列CuO含量不同(质量分数: 50%-80%)的CuO-TiO2-ZrO2复合氧化物, 并利用X射线衍射(XRD)、氮吸附(BET)、程序升温还原(H2-TPR)、程序升温脱附(H2/CO2-TPD)和氧化亚氮(N2O)反应吸附等多种方法对其进行了表征. 以所制备的CuO-TiO2-ZrO2为甲醇合成活性组分与HZSM-5分子筛进行机械混合制成双功能催化剂CuO-TiO2-ZrO2/HZSM-5, 在微型固定床流动反应器中, 于250°C、3.0 MPa、H2/CO2(体积比2.8)以及空速1500 mL·g-1·h-1的条件下, 对其催化CO2加氢直接合成二甲醚(DME)的性能进行了评价.结果表明: 随着CuO-TiO2-ZrO2中CuO含量的增加, CO2的转化率先逐渐增大, 至70%时达到最大, 之后反而降低. DME的选择性随着催化剂中CuO含量的增加而增加, 至≥70%时基本不变, 故当CuO含量为70%时, DME的收率达到最大值(13.2%). 催化剂上合成含氧化合物(甲醇和DME)的活性与催化剂中金属铜的比表面积之间有较好的对应关系.

关键词: CO2加氢, 二甲醚, CuO-TiO2-ZrO2复合氧化物, HZSM-5分子筛, 双功能催化剂

Abstract: A series of CuO-TiO2-ZrO2 mixed oxides with different CuO mass fractions (50%-80%) were prepared by co-precipitation and characterized by X-ray diffraction (XRD), N2 physisorption, temperatureprogrammed reduction of hydrogen (H2-TPR), temperature-programmed desorption of carbon dioxide (CO2-TPD) and hydrogen (H2-TPD), and reactive N2O adsorption techniques. The prepared CuO-TiO2-ZrO2 samples were mixed physically with HZSM-5 zeolite to synthesize dimethyl ether (DME) from CO2 hydrogenation in a fixed bed reactor at 250°C, 3.0 MPa, gas hourly space velocity (GHSV) of 1500 mL·g-1· h-1, and volume ratio of 2.8 for H2 to CO2. We found that the conversion of CO2 increased with an increase in CuO content, reached a maximum at a CuO content of 70% and then decreased. The selectivity of DME increased with an increase in CuO content initially and remained essentially constant when the CuO content was ≥70%. Thus, the yield of DME reached a maximum of 13.2% at 70% CuO content. The productivity of the oxygenated compounds (including methanol and DME) on the CuO-TiO2-ZrO2/HZSM-5 catalysts is closely related to the metallic copper surface area.

Key words: Hydrogenation of CO2, Dimethyl ether, CuO-TiO2-ZrO2 mixed oxide, Zeolite HZSM-5, Bifunctional catalyst