Acta Phys. -Chim. Sin. ›› 2008, Vol. 24 ›› Issue (07): 1264-1270.doi: 10.3866/PKU.WHXB20080724

• ARTICLE • Previous Articles     Next Articles

Electrochemical Reduction Behaviors of Maleic Acid and Fumaric Acid at Lead Electrode

SHAO Heng; GAN Yong-Ping; HUANG Hui; ZHANG Wen-Kui   

  1. College of Chemical Engineering and Materials Science, Zhejiang University of Technology, Hangzhou 310032, P. R. China
  • Received:2007-12-05 Revised:2008-03-21 Published:2008-07-04
  • Contact: ZHANG Wen-Kui E-mail:chem@zjut.edu.cn

Abstract: Electrochemical reduction characteristics of fumaric acid (FA) and maleic acid (MA) at lead electrode were investigated by voltammetry, chronocoulometry, and electrochemical impedance spectrum (EIS). The corresponding transfer coefficients, apparent energies of activation, and diffusion coefficients were calculated and the mechanism of electrochemical reduction were discussed. The experimental results showed that the electrochemical reduction of FA and MA was two-electron irreversible reaction, in which the diffusion process was the rate-determined step. The reductive potential of FA at lead was about 0.1 V higher than that of MA, indicating that FA is more difficult to be electroreduced. The corresponding diffusion coefficients for 0.04 mol·L-1 FA and MA in 0.1 mol·L-1 sulphuric acid solution were 7.96×10-6 and 6.72×10-6 cm2·s-1, respectively. The EIS results showed that charge transfer was the rate-determined step in the electroreduction processes of FA and MA at Pb electrode under low DC bias. As increase in bias potential, the diffusion process became the rate-determined step gradually. The difference in the electroreduction characteristics of FA and MA at Pb electrode was due to their different three-dimensional structure.

Key words: Maleic acid, Fumaric acid, Electrochemical behaviour, Diffusion

MSC2000: 

  • O646