化学学报 ›› 2010, Vol. 68 ›› Issue (19): 2013-2018. 上一篇    下一篇

研究简报

甲醇与一氧化碳合成甲酸甲酯反应机理的理论研究

唐新村*,1,2,曾智文1,蒋历辉1,2,陈亮1,王志敏1,贾殿赠3   

  1. (1中南大学化学化工学院 长沙 410083)
    (2中南大学粉末冶金国家重点实验室 长沙 410083)
    (3新疆大学化学化工学院 乌鲁木齐 830046)
  • 投稿日期:2009-07-28 修回日期:2010-03-31 发布日期:2010-05-13
  • 通讯作者: 唐新村 E-mail:tangxincun@163.com
  • 基金资助:

    国家自然科学基金No.20676152;国家自然科学基金No.20876178

A Theoretical Study on the Reaction Mechanism of Methanol with Carbon Monoxide to Form Methyl Formate

Tang Xincun*,1,2 Zeng Zhiwen1 Jiang Lihui1,2 Chen Liang1 Wang Zhimin1 Jia Dianzeng3   

  1. (1 School of Chemistry and Chemical Engineering, Central South University, Changsha 410083)
    (2 State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083)
    (3 School of Chemistry and Chemical Engineering, Xinjiang University, Urumqi 830046)
  • Received:2009-07-28 Revised:2010-03-31 Published:2010-05-13

用密度泛函理论(DFT)研究了甲醇与一氧化碳的微观反应机理. 在B3LYP/6-311++G(d,p)水平上优化了反应物、过渡态及产物的几何构型, 并通过振动分析和内禀反应坐标方法(IRC)分别确认了过渡态的结构与反应途径. 在CCSD/6-311++G(d,p)水平上进行能量校正, 并根据计算的势能面探讨了CH3OH+CO反应机理. 结果表明, CH3OH+CO反应体系有三个可能的反应通道, 产物分别为甲酸甲酯、乙酸、羟基乙醛. 在无催化条件下, 计算得到生成甲酸甲酯、乙酸和羟基乙醛的反应活化能分别是364.715, 460.775和611.402 kJ•mol-1, 生成甲酸甲酯和羟基乙醛的反应为吸热反应, 而生成乙酸的反应为放热反应.

关键词: CH3OH+CO, 甲酸甲酯, 反应机理, 过渡态, 密度泛函理论

The microcosmic reaction mechanism of methanol and carbon monoxide was studied by density functional theory (DFT). Then, the geometries of the reactants, transition states and products were optimized by using B3LYP method with 6-311++G(d,p) basis set. Vibration analysis and intrinsic reaction coordinate (IRC) method were employed to confirm the structure of transition state and search the reaction path, respectively. The energies of the species were corrected at the CCSD/6-311++G(d,p) level and the possible reaction mechanism of CH3OH+CO was proposed. Three probable reaction channels were found with the products respectively as methyl formate, acetic acid and glycollic aldehyde. Results showed that product as methyl formate (without any catalyst) was the dominant reaction channel with the activation energy of 364.715 kJ•mol-1, which is relatively lower than that for acetic acid (460.775 kJ•mol-1) and glycollic aldehyde (611.402 kJ•mol-1). In addition, the energy calculations show that the formations of methyl formate and glycollic aldehyde are endothermic reaction while product as acetic acid is exothermic one.

Key words: CH3OH+CO, methyl formate, reaction mechanism, transition states, DFT