Abstract: The invention provides processes that significantly reduce acid consumption while maintaining efficient leach recovery of copper from oxide and acid consuming ores. The invention provides a hydrometallurgical process that reduces acid required for leaching in the presence of a solid ion exchange media. The presence of the ion exchanger leads to copper extraction from solution into the ion exchange phase, the removal of the copper from solution shifts the dissolved copper equilibrium, enabling additional copper dissolution at weak acidities where normally the leaching equilibrium would be hindered. In select embodiments, the process is not reliant on an external neutralising agent to control pH but rather on the acid consuming characteristic of the ore being processed and a limit to the amount of acid added. At the pH at which the leach is controlled, iron (if present) is predominantly present as the ferrous ion, which has a lower affinity for the resin than copper.

Abstract: A process for the treatment of solutions or slurries containing dissolved metals comprises the steps of (a) contacting the solution or slurry with an ion exchange resin that selectively removes one or more dissolved metals from the solution or slurry wherein the solution or slurry and the resin are introduced into a vessel or column via sub-surface means, (b) separating loaded resin from the solution or slurry, (c) eluting the one or more metals from the loaded resin with an eluting agent, (d) separating the eluting solution containing eluted metal ions from the resin; and (e) transferring regenerated resin from step (d) back to step (a).