Thermodynamic analysis of gold leaching by ammoniacal thiosulfate using Eh/pH and speciation diagrams

Authors
Aylmore, MG Muir, DM
Citation
Mg. Aylmore et Dm. Muir, Thermodynamic analysis of gold leaching by ammoniacal thiosulfate using Eh/pH and speciation diagrams, MIN MET PR, 18(4), 2001, pp. 221-227
Citations number
23
Categorie Soggetti
Geological Petroleum & Minig Engineering
Journal title
MINERALS & METALLURGICAL PROCESSING
ISSN journal
07479182 → ACNP
Volume
18
Issue
4
Year of publication
2001
Pages
221 - 227
Database
ISI
SICI code
0747-9182(200111)18:4<221:TAOGLB>2.0.ZU;2-6
Abstract
Thiosulfate offers a nontoxic alternative to cyanide for processing gold or es. The mechanism of leaching gold using ammoniacal thiosulfate solution is 2 driven by the Cu(II)-Cu(I) redox couple and is complicated by competing ligands such as NH3 and S2O32-. It is shown that an understanding of the co pper speciation and sulfur speciation is required to optimize this system. This paper presents Eh-pH and speciation diagrams for varying concentration s of Cu(II), S2O32- and NH3 and discusses the conditions under which variou s copper and sulfur species are stable.