Copper extraction electrowinning

Kordosky, G. A. (2002) Copper recovery using leach/solvent extraction/electrowinning technology forty years of innovation, 2.2 million tonnes of copper annually, in International Solvent Extraction Conference, Cape Town, South Africa, Mar. 17-21, 2002. 

Cuprex [Copper extraction] A process for extracting copper from sulfide ores, combining chloride leaching, electrowinning, and solvent extraction. Piloted by a consortium consisting of ICI, Nerco Minerals Company, and Tecnicas Reunidas. 

Since the mid-1960s, solvent extraction has been applied on a commercial scale to the recovery of copper from aqueous solutions obtained from the leaching of acid-soluble copper ores with dilute sulfuric acid. At present, several plants producing up to 200 t of copper per day by an integrated leach—solvent extraction—electrowinning route are in operation throughout the world. 

Compare and contrast the niches served in copper recovery and production by froth flotation, hot smelting, hydrometallurgical extraction, electrowinning, and cementation. Include consideration of environmental factors. 

Small plastic balls in layers on top on the cell were first introduced to suppress acid mist in copper. The first commercial Solvent Extraction - Electrowinning (SX-EW) plant, at Ranchers Bluebird in Arizona (1970) claimed the use of a thin layer of kerosene (Napoleum 470) as a mist suppressant on top of the electrolyte [3]. Besides the advantage of suppressing acid mist. Ranchers also claimed that this kerosene would also collect organic carryover from the SX plant so as not to have organic bum on the top sections of the copper cathode. Plastic beads (or BB s), that were much smaller than plastic balls (see Figure 1) were first used at Magma San Manuel in Arizona in the late 1980 s and then later in other North American and Australian SX-EW plants. 

Davis, J.R. (ed.) (2001) ASM specialty Handbook. Coptper and Copper Alloys. ASM, Materials Park, OH. Gerald, V.,J. (ed.) (1999) Copper Leaching, Solvent Extraction Electrowinning Technology. Society for Mining Metallurgy Exploration, Littleton, CO. 

The development of selective extractants for copper has made extraction from dilute solutions (1—5 kg/m ) economically feasible. Transfer of the copper by stripping to a more concentrated sulfuric acid solution, ie, 30—40 kg/m for Cu " and 150—170 kg/m for H2SO4, from which the copper is recovered by electrowinning. The simplified reaction,... 

Copper. Copper is economically extracted by smelting of a chalcopyrite concentrate. A copper electrowinning process was developed commercially in 1912 for the treatment of lean ores. It is also suitable for treatment of copper oxide or sulfate obtained by roasting of the concentrate. 

Electrowinning. Vat leaching often yields copper solutions having concentrations sufficiently high for direct electrowinning. However, high concentrations of cations other than copper and low copper concentrations make it more difficult to obtain high purity electrolytic copper by direct electrolysis of leach solutions than by electrolysis of purified solutions obtained from solvent extraction. 

Increasingly more copper is being produced by electrowinning because of economics and technical advances, such as in solvent extraction processes. Certain brands obtained by SX—EW are treated as cathode quahty and are used directly by wire-rod manufacturers. Whereas in 1984 100,180 t of copper was electrowon in SX—EW plants, in 1992, 439,043 t produced by SX—EQ was electrowon (7). 

In the most common hydrometallurgical process, the ore is leached with ammonia or sulfuric acid to extract the copper. These processes can operate at atmospheric pressure or as pressure leach circuits. Copper is recovered from solution by electrowinning, a process similar to electrolytic refining. The process is most commonly used for leaching low-grade deposits in situ or as heaps. 

The application of solvent extraction to copper recovery has been a major growth area since the last review of this series.11,13 Almost 30% of world production in 2000 involved the use of sulfuric acid heap leaching, solvent extraction, and electrowinning, far exceeding earlier predictions.136... 

Figure 5 A simplified flowsheet and materials balance for the recovery of copper from oxidic and transition ores by heap leaching, solvent extraction and electrowinning.

Arbiter Previously known as the Sherritt-Gordon ammonia process. A process for leaching copper from sulfide concentrates, using ammoniacal ammonium sulfate solution at 85°C and relying on air oxidation. Copper is produced from the leachate by solvent extraction and electrowinning. Sulfur is recovered as ammonium sulfate. Operated on a large scale by the Anaconda Copper Company in Montana from 1974 to 1979. See Sherritt-Gordan. 

Cymet (1) [Cyprus Metallurgical] A process for extracting copper from sulfide ores. It involves leaching, solvent extraction, and electrowinning. Developed by the Cyprus Metallurgical Processes Corporation, Golden, CO. Superseded by Cymet (2). 

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