Acta Phys. -Chim. Sin. ›› 2008, Vol. 24 ›› Issue (11): 2059-2064.doi: 10.3866/PKU.WHXB20081121

• ARTICLE • Previous Articles     Next Articles

Mechanism of the Copper-Catalyzed Water Gas Shift Reaction

MAO Jiang-Hong; NI Zhe-Ming; PAN Guo-Xiang; XU Qian   

  1. College of Chemical Engineering and Materials Science, Zhejiang University of Technology, Hangzhou 310032, P. R. China
  • Received:2008-07-22 Revised:2008-08-21 Published:2008-11-10
  • Contact: NI Zhe-Ming E-mail:jchx@zjut.edu.cn

Abstract: A detailed density functional theory (DFT) investigation revealed three possible micro-mechanisms of the water-gas shift reaction catalyzed by copper. Geometries of stationary points (reactants, intermediates, transition states and products) were optimized with the self-consistent Perdew-Wang-91 generalized gradient approximation (GGA-PW91) method. All transition states were verified by the frequency analysis method. Results showed that the formate mechanismhad a lowprobability, while the carboxyl mechanismand the redox mechanismwere more probable. During the carboxyl mechanism, the intermediate COOH(s) was formed followed by its decomposition via disproportionation with OH (s). The calculated activation energy barrier for the carboxyl mechanism was 3.8 kJ·mol-1, which was lower than that for the redox mechanism.

Key words: Water gas shift reaction, Reaction mechanism, Density functional theory, Transition state

MSC2000: 

  • O641