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Electrochemical kinetics of gold dissolving in alkaline thiourea solution

  • Chai Li-yuan 
  • Wang Yun-yan Email author
Article
  • 86 Downloads

Abstract

Kinetic parameters of the electrode reactions were measured by investigating steady-state current-potential behaviors. The results show that the apparent transfer coefficient of anodic process is 0.0582, diffusion coefficient of thiourea gold complex is 6.04 × 10−6 cm2/s, anodic reaction order of thiourea is 2.0183, and anodic reaction order of OH is 0.0166. The theoretical kinetics equation of gold dissoving in alkaline thiourea solution is deduced, which indicates that anodic reaction order of thiourea is 2, and anodic reaction order of OH is 0. The theoretical values of the kinetic parameters are consistent with experimental values very well. The correctness of the mechanism is further demonstrated using apparent transfer coefficient according to the electrochemical dynamic equation of multi-electron reaction.

Key words

gold alkaline thiourea electrochemical kinetics 

CLC number

TF801 

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Copyright information

© Science Press 2001

Authors and Affiliations

  1. 1.School of Metallurgical Science and EngineeringCentral South UniversityChangshaChina

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