Solvent extraction and electrowinning

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Solvent extraction and electrowinning (SX/EW) is a two-stage hydrometallurgical process that first extracts and upgrades copper ions from low-grade leach solutions into a solvent containing a chemical that selectively reacts with and binds the copper in the solvent. The copper is extracted from the solvent with strong aqueous acid which then deposits pure copper onto cathodes using an electrolytic procedure (electrowinning).

SX/EW processing is best known for its use by the copper industry, where it accounts for 20% of worldwide production, but the technology is also successfully applied to a wide range of other metals including cobalt, nickel, zinc and uranium.

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Extractive metallurgy is a branch of metallurgical engineering wherein process and methods of extraction of metals from their natural mineral deposits are studied. The field is a materials science, covering all aspects of the types of ore, washing, concentration, separation, chemical processes and extraction of pure metal and their alloying to suit various applications, sometimes for direct use as a finished product, but more often in a form that requires further working to achieve the given properties to suit the applications.

Chino mine

The Chino Mine, also known as the Santa Rita mine, also known as Santa Rita del Cobre, is an open-pit porphyry copper mine located in the town of Santa Rita, New Mexico 15 miles (24 km) east of Silver City. The mine was started as the Chino Copper Company in 1909 by mining engineer John M. Sully and Spencer Penrose, and is currently owned and operated by Freeport-McMoRan Inc. subsidiaries. The area where the mine is located is at an average elevation of 5,699 feet (1,737 m).

Copper extraction Process of extracting copper from the ground

Copper extraction refers to the methods used to obtain copper from its ores. The conversion of copper consists of a series of physical and electrochemical processes. Methods have evolved and vary with country depending on the ore source, local environmental regulations, and other factors.

Green chemistry, also called sustainable chemistry, is an area of chemistry and chemical engineering focused on the design of products and processes that minimize or eliminate the use and generation of hazardous substances. While environmental chemistry focuses on the effects of polluting chemicals on nature, green chemistry focuses on the environmental impact of chemistry, including lowering consumption of nonrenewable resources and technological approaches for preventing pollution.

Codelco Chilean copper company

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Hydrometallurgy is a technique within the field of extractive metallurgy, the obtaining of metals from their ores. Hydrometallurgy involve the use of aqueous solutions for the recovery of metals from ores, concentrates, and recycled or residual materials. Processing techniques that complement hydrometallurgy are pyrometallurgy, vapour metallurgy, and molten salt electrometallurgy. Hydrometallurgy is typically divided into three general areas:

Electrowinning Electrolytic extraction process

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The transfer is driven by chemical potential, i.e. once the transfer is complete, the overall system of chemical components that make up the solutes and the solvents are in a more stable configuration. The solvent that is enriched in solute(s) is called extract. The feed solution that is depleted in solute(s) is called the raffinate. LLE is a basic technique in chemical laboratories, where it is performed using a variety of apparatus, from separatory funnels to countercurrent distribution equipment called as mixer settlers. This type of process is commonly performed after a chemical reaction as part of the work-up, often including an acidic work-up.

Skorpion Zinc

Skorpion Zinc is a zinc mine in the ǁKaras Region of southern Namibia, producing Special High Grade (SHG) zinc. The mine is situated near Rosh Pinah. It was established at a cost of US$450 million by Anglo American in 2003. It is the tenth-largest zinc mine in the world, and the largest employer in Rosh Pinah, providing 1,900 jobs.

In situ leach

In-situ leaching (ISL), also called in-situ recovery (ISR) or solution mining, is a mining process used to recover minerals such as copper and uranium through boreholes drilled into a deposit, in situ. In situ leach works by artificially dissolving minerals occurring naturally in a solid state. For recovery of material occurring naturally in solution, see: Brine mining.

The Whim Creek Copper Mine is an operating copper oxide mine, located in the City of Karratha in the Pilbara region of Western Australia.

Toquepala mine

The Toquepala mine is a large porphyry copper mine in the Tacna Province, Tacna Department, Peru. The mine is an open-pit mine producing copper, molybdenum, rhenium and silver with minor gold and zinc.

Bwana Mkubwa is a settlement and a mine in Copperbelt Province, Zambia. It is the oldest mine in Zambia's Copperbelt region. As a settlement with no municipal status, it became a locale due to the abundant copper deposits found in the area. Today, it is part of Ndola.

The Ruashi Mine is an open-pit copper and cobalt mine operated by Metorex that is located about 10 kilometres (6.2 mi) from Lubumbashi in Katanga Province, Democratic Republic of the Congo. The project includes a plant to concentrate the ore from the Ruashi and Etoile mines, and a modern solvent extraction electrowinning (SX-EW) processing plant. As of 2008, annual capacity was estimated to be 10,000 tonnes of copper and 1,000 tonnes of Cobalt.

The Etoile Mine is an open-pit copper mine on the outskirts of Lubumbashi in Katanga Province of the Democratic Republic of the Congo (DRC). Chemaf owns the license. Chemaf is 95% owned by Shalina Resources and 5% by the DRC government.

Non-ferrous extractive metallurgy Metallurgy process

Non-ferrous extractive metallurgy is one of the two branches of extractive metallurgy which pertains to the processes of reducing valuable, non-iron metals from ores or raw material. Metals like zinc, copper, lead, aluminium as well as rare and noble metals are of particular interest in this field, while the more common metal, iron, is considered a major impurity. Like ferrous extraction, non-ferrous extraction primarily focuses on the economic optimization of extraction processes in separating qualitatively and quantitatively marketable metals from its impurities (gangue).

Escondida

Escondida is a copper mine at 3,100 metres (10,200 ft) elevation in the Atacama Desert in Antofagasta Region, Chile.

Jameson cell Machinery for processing minerals

The Jameson Cell is a high-intensity froth flotation cell that was invented by Laureate Professor Graeme Jameson of the University of Newcastle (Australia) and developed in conjunction with Mount Isa Mines Limited.

IsaKidd refining technology

The IsaKidd Technology is a copper electrorefining and electrowinning technology that was developed independently by Copper Refineries Proprietary Limited (“CRL”), a Townsville, Queensland subsidiary of MIM Holdings Limited, and at the Falconbridge Limited (“Falconbridge”) now-dismantled Kidd Creek refinery that was at Timmins, Ontario. It is based around the use of reusable cathode starter sheets for copper electrorefining and the automated stripping of the deposited “cathode copper” from them.

Mineral processing and extraction of metals are very energy-intensive processes, which are not exempted of producing large volumes of solid residues and wastewater, which also require energy to be further treated and disposed. Moreover, as the demand for metals increases, the metallurgical industry must rely on sources of materials with lower metal contents both from a primary and/or secondary raw materials. Consequently, mining activities and waste recycling must evolve towards the development of more selective, efficient and environmentally friendly mineral and metal processing routes.

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