Abstract: A process for producing one or more metals from a mineral feedstock (12) is defined. The mineral is fed to a leaching apparatus (10) wherein it is contacted with electrolyte (14). The leaching apparatus has zones of decreasing oxidation potential (17, 18, 19, 20) respectively. A stream of electrolyte (14A) is removed from zone (20) and is treated to remove impurities and unwanted metals in treatment unit (25A), prior to metal recovery by electrolysis. The electrolyte after electrolysis is then returned to the leaching unit (10). A second electrolyte stream (14B) may be removed from zone (19) for recovery of additional metals. The electrolyte (14B) is treated to remove impurities and any unwanted metals in treatment unit (25B), prior to metal recovery by electrolysis. The electrolyte after electrolysis is returned to leaching unit (10). The process enables the leaching of difficult to leach minerals, including gold, and can produce one or more metals of high purity.

Abstract: Recovering zinc from zinc bearing ore or concentrate (1) in an electrolic cell (3) which includes a cathode (5) containing cathode compartment (16) and an anode (4) containing anode compartment (2). The cathode and anode compartments are defined by interposing between such compartments an ion-selective membrane (6) capable of preventing migration of ionic copper from anode compartment (2) to cathode compartment (16). Process includes forming in anode compartment (2) a slurry of ore or concentrate (1) with a chloride and copper-ion containing solution, intimately mixing oxygen bearing gas (7) with the slurry, maintaining the mixture substantially at atmospheric pressure and at a temperature up to the boiling point of the solution, and maintaining the pH of the mixture from 1 to 4. The resultant solution is rich in solubilized zinc. At least a portion of the mixture is withdrawn and resultant solution (12) separated therefrom.

Abstract: An electrolytic cell for recovery of metal from mineral ores or concentrates comprising a tank for holding a slurry of electrolyte and the mineral ore or concentrates. Vertical anodes are radially disposed in the tank and vertical cathodes enclosed in diaphragm bags are interposed between the anodes. Agitating means are located in the tank below the anodes and cathodes. Metal is removed from a central collecting container in the tank by pump means.

Abstract: Lead is selectively recovered electrolytically from a mixture of metal sulphides in an aqueous chloride electrolyte by controlling the rate of agitation and oxidation conditions so that metal sulphides other than lead remain substantially undissolved.

Abstract: The invention provides a process for extracting a base metal from a base metal bearing ore or concentrate which includes forming a slurry of the ore or concentrate with an electrolyte containing chloride ions and copper ions, oxygenating the mixture and maintaining the pH of the mixture from 1.5 to 7.0. Iron impurities will be substantially precipitated as ferric oxide and may be recovered, sulphide sulphur will be converted to elemental form and can be recovered and the base metal is taken into solution. The base metal can be recovered by electrolysis which can also produce hydrogen ions for pH maintenance. The copper ions can be precipitated by the addition of fresh ore or concentrate and can be recycled. The process is preferably carried out in a counter-current manner in which electrolyte containing increasing amounts of the base metal in solution is conveyed counter-current to solids which decrease in base metal content.

Abstract: This process concerns the direct electroconversion of low grade manganese ores to high purity manganese dioxide product, which, among other applications, is ideally suited for use in dry cells. The process operating conditions are controlled such that impurities in the ore are substantially eliminated from the product. A decrease in impurity levels in excess of 100 fold can be achieved between the product and the ore feed.