Process for regenerating thiosulphate from a gold leaching stream

摘要

A new process of regenerating thiosulphate from a spent thiosulphate solution comprises the steps of: (a) reacting the spent thiosulphate solution with sulphide to produce elemental sulphur and a regenerated thiosulphate solution, (b) separating the elemental sulphur from the regenerated thiosulphate solution, (c) biologically reducing the separated elemental sulphur to produce sulphide, and (d) returning the sulphide from step (c) to step (a). ??This can be applied in a process of extracting noble metals such as gold from a gold-containing slurry by contacting the slurry with a solution containing thiosulphate ions and oxygen to produce a gold thiosulphate solution, contacting the gold thiosulphate solution with an absorbent to produce a gold-loaded absorbent and spent thiosulphate, recovering gold from the gold-loaded absorbent, and regenerating the thiosulphate as described above.