化工学报 ›› 2016, Vol. 67 ›› Issue (4): 1340-1347.DOI: 10.11949/j.issn.0438-1157.20150424

• 催化、动力学与反应器 • 上一篇    下一篇

乙炔电还原制备乙烯的反应机理

宋秀丽1,2, 贾瑞龙1, 解学佳1, 梁镇海1, 朱珍平3   

  1. 1. 太原理工大学化学化工学院, 山西 太原 030024;
    2. 太原师范学院化学系, 山西 太原 030031;
    3. 中国科学院山西煤炭化学研究所煤转化国家重点实验室, 山西 太原 030001
  • 收稿日期:2015-04-07 修回日期:2015-11-24 出版日期:2016-04-05 发布日期:2016-04-05
  • 通讯作者: 梁镇海
  • 基金资助:

    国家自然科学基金委员会与神华集团有限责任公司联合资助项目(U1261103);中国科学院山西煤炭化学研究所煤转化国家重点实验室开放基金项目(J12-13-913)。

Reaction mechanism of electrochemical reduction of acetylene to ethylene

SONG Xiuli1,2, JIA Ruilong1, XIE Xuejia1, LIANG Zhenhai1, ZHU Zhenping3   

  1. 1. College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China;
    2. Department of Chemistry, Taiyuan Normal University, Taiyuan 030031, Shanxi, China;
    3. State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, Shanxi, China
  • Received:2015-04-07 Revised:2015-11-24 Online:2016-04-05 Published:2016-04-05
  • Supported by:

    supported by the National Natural Science Foundation of China and Shenhua Group Corp.(U1261103) and the Open Fund of State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences (J12-13-913).

摘要:

选择钯电还原乙炔制备乙烯并通过气相色谱法对产品进行表征,利用第一性原理计算方法探讨乙炔在催化剂Pd (111)表面的吸附情况,采用循环伏安法研究钯电极在硫酸溶液中还原乙炔的电极过程,测定电极的稳态极化曲线并根据极化曲线推算Tafel斜率,重点结合表观传递系数及反应级数对拟定的乙炔电还原制备乙烯的反应机理进行验证。实验结果表明:乙炔分子在Pd (111)面上呈平行桥键构型时最稳定;钯电极在硫酸溶液中可将乙炔电还原为乙烯;得出了反应最可能的速率控制步骤。

关键词: 乙炔, 乙烯, 吸附, 还原, 电化学机理, 第一性原理, 速率控制步骤

Abstract:

Electrochemical synthesis of ethylene from acetylene was put forward and the synthesized ethylene was characterized by gas chromatography (GC). First-principle calculations were carried out to examine the adsorption of acetylene over the Pd (111) surface. The electrochemical reduction behavior of acetylene has been investigated on a Pd electrode by cyclic voltammetry (CV) and stable polarization curves in sulfuric acid. The formation mechanism of ethylene in the sulfuric acid was proposed and the transfer coefficients of the reaction were calculated. The results showed that the acetylene molecule tended to be adsorbed through the threefold parallel-bridge configuration that was computed to be the most stable because of its lowest adsorption energy. The rate-determining step in the electrolysis process has been obtained. The rate of this step obtained from the assumed process agreed well with the experiment results.

Key words: acetylene, ethylene, absorption, reduction, electrochemistry mechanism, first-principles, rate-determining step

中图分类号: