An electrochemical study of the dissolution of gold in thiosulfate solutions Part I: Alkaline solutions

Suchun Zhang; Nicol, M. J.
September 2003
Journal of Applied Electrochemistry;Sep2003, Vol. 33 Issue 9, p767
Academic Journal
The anodic dissolution of gold in alkaline thiosulfate solutions has been studied by using a rotating gold disc. Experimental results have shown that the gold dissolves at measurable rates in thiosulfate solutions at potentials above 0.2 V. It has been confirmed that dissolution occurs in parallel with oxidation of thiosulfate with a dissolution current efficiency that varies with time and with the experimental conditions and which is generally in the range of 0.3 to 0.6. Although oxygen could be used as an oxidant for gold in the thiosulfate system, the rate of the cathodic reduction of oxygen in the relevant potential region is too slow for practical purposes. It was found that in the potential region investigated, thiosulfate ions undergo oxidative decomposition leaving a sulfur-like film on the surface of gold, which inhibits the rate of dissolution of gold and results in a low anodic current efficiency for the dissolution of gold. The factors (temperature, pH, thiosulfate concentration and ammonia) have been found to have positive effects on the kinetics of gold dissolution. The rates of gold dissolution in oxygenated alkaline thiosulfate solutions have been estimated to be much lower than in the copper–ammonia–thiosulfate and cyanide systems.


Related Articles

  • Preparation and electrochromic properties of V–Nb mixed-oxide films by evaporation. Chen, W.; Kaneko, Y.; Kinomura, N. // Journal of Applied Electrochemistry;Jun2003, Vol. 33 Issue 6, p515 

    Focuses on preparation and electrochromic properties of V-Nb mixed-oxide films by evaporation. Investigation of pentoxide vanadium materials; Experimental details.

  • The electrical n- p phase transition in the Sb0.92V0.92O4 and Sb2V2O9 compounds. Groń, T.; Krajewski, A.; Duda, H.; Filipek, E. // Journal of Materials Science;Oct2005, Vol. 40 Issue 19, p5299 

    Examines the electrical phase transition in antimony and vanadium compounds. Consideration of a new class of catalysts that are active and selective in ammoxidation of propane to acrylonitrile; Crystallization of the compound in a tetragonal system; Occurrence of chemical reactions; Electrical...

  • Zinc oxide nanorods grown on two-dimensional macroporous periodic structures and plane Si as a pH sensor. Al-Hilli, Safaa M.; Al-Mofarji, R. T.; Klason, P.; Willander, M.; Gutman, N.; Sa'ar, A. // Journal of Applied Physics;Jan2008, Vol. 103 Issue 1, p014302 

    pH determination is a strong prerequisite for many biochemical and biological processes. We used two methods, namely, the electrochemical potential method (experimental) and site binding method (theoretical), to study the sensitivity of zinc oxide (ZnO) nanorods grown on two-dimensional...

  • Carbon-nanotube tips with edge made of a transition metal. Mpourmpakis, Giannis; Froudakis, George E.; Andriotis, Antonis N.; Menon, Madhu // Applied Physics Letters;11/7/2005, Vol. 87 Issue 19, p193105 

    We show that transition metal atoms, when in contact with the open ends of single-wall carbon nanotubes can form stable tip structures. This allows one to combine the superior elastic and mechanical behavior of the nanotubes with the excellent electronic and electrical properties of transition...

  • Editorial. Wragg, A. A. // Journal of Applied Electrochemistry;Jul2008, Vol. 38 Issue 7, p881 

    The article discusses the subject of articles published within the issue, which refers to the papers from the conference GEI-ERA 2007 on environmental and energy related issues in electrochemistry.

  • Influence of cobalt ions on the anodic oxidation of a lead alloy under conditions typical of copper electrowinning. Nguyen, T.; Guresin, N.; Nicol, M.; Atrens, A. // Journal of Applied Electrochemistry;Feb2008, Vol. 38 Issue 2, p215 

    The influence of cobalt ions in the solution on the anodic oxidation of a commercial Pb–Ca–Sn alloy under conditions typical of copper electrowinning was studied using cyclic voltammograms and potential decay transients. The cobalt ions changed the structure, morphology and...

  • Theoretical studies of the first- and second-row transition-metal mono- and dicarbonyl positive ions. Barnes, Leslie A.; Rosi, Marzio; Bauschlicher, Charles W. // Journal of Chemical Physics;7/1/1990, Vol. 93 Issue 1, p609 

    Ab initio calculations have been carried out on the first- and second-row transition-metal mono- and dicarbonyl positive ions. The bonding in these systems is discussed in detail. Trends in the series of mono- and dicarbonyl ions and between the first- and second-row transition metals are...

  • Preparation of lead sulfide nanoparticles in the photolysis of aqueous solutions of lead thiosulfate complex. Egorov, N.; Eremin, L.; Usov, V.; Larionov, A. // High Energy Chemistry;Jul2007, Vol. 41 Issue 4, p251 

    It was found from spectroscopic and microscopic data that lead sulfide nanoparticles are formed during the UV irradiation of aqueous solutions of lead thiosulfate complex. The yield and the size of the lead sulfide nanoparticles depend on the concentration of solution and the lead to thiosulfate...

  • sodium thiosulfate.  // Hutchinson Dictionary of Scientific Biography;2005, p1 

    Correct chemical name for sodium hyposulfite (hypo), the substance used to fix photographic images after developing.


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics