The thermodynamic analysis of chemical transformations in dissolving gold in the cyanic solutions made on the basis of plasma-chemically treated water
DOI:
https://doi.org/10.15276/opu.1.43.2014.43Keywords:
contact nonequilibrium low-temperature plasma, cyanide solutions, gold, oxidation-reduction/redox potentialAbstract
Usage of traditional techniques of extracting gold by cyanidation is accompanied by increased costs for certain manufacturing operations. The paper is devoted to the thermodynamic analysis of gold dissolution in cyanide solutions made on the basis of plasmochemically activated water. It is established that рН value affects the process of gold dissolution by the cyanide solutions prepared with the use of water treated by the contact nonequilibrium low-temperature plasma. Gibbs energy change for a pair of redox reactions in the system under study has the form of a function with a pronounced minimum at рН=9,30 (∆G=-2050 kJ/mol), and an excess at рН=11,63 (∆G=-1950 kJ/mol).
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References
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