Extraction of Copper

Copper occurs in nature in combined form as well as pure metallic form. The most primitive metals are Copper, identified to the human race. Copper gets its name from cuprum as initiated by Romans, for Copper was first gotten from Cyprus Island. Ores from where one can get Copper are cuprite or ruby copper, copper glance, and copper pyrite. However, the main ore is copper pyrite, which generates around 76% of the total quantity of Copper for the whole world. In India, the places like Tamil Nadu, Rajasthan (Khetri and Darbia), and Bihar (Singhbhum) are the main source of Copper. 

Properties of Copper

Copper has certain properties or characteristics that make it unique in its sense. These properties are:

• It is soft, pliable, and elastic

• It has high electrical and thermal conductivity

• Its most pure form is of pinkish-orange colour

• It is very lustrous and generally reddish-brown

• It has a high melting point of 1356 degrees Celsius

• It also has high density

• It can get a green coating of copper carbonate when exposed to carbon dioxide or moisture

Utilities of Copper

Like any other metal, it has several utilities that help produce various things. Some of these utilities are as follows:

• Copper is applied in the role of building material

• Copper being a good conductor of electricity is used in electric wires

• Copper is also applied to plumbing, for it can bend easily and does not have a reaction with water

• Copper is a good heat conductor, so it is used in boilers

• Copper is used in motor parts for its excellent conductivity of electricity

• Copper is applied in industrial machines to assist in the exchange of heat

• Copper is installed in roofing for it is long-running and does not require much maintenance

Ores of Copper

Ores from where one can get Coppers are cuprite or ruby copper, copper glance, and copper pyrite. However, most ores only have a small quantity of Copper except for copper pyrite. The leftover ore contains gangue without any market value. The main intent of any metallurgical treatment is the division of minerals of ore from the minerals of the gangue inside the main rock.

Extraction of Copper

The process of extracting copper from its ore is called the copper extraction process. The extraction of Copper contains physical and electrochemical procedures. Depending on the nature of the ore, the source of the ore, and the rules of a particular country, the copper extraction process differ accordingly. 

Process of Extraction of Copper

There are many steps followed in the extraction of copper from its ores. These are:

1. Concentrating

2. Roasting

3. Smelting

4. Bassemerizating

5. Refining

Concentrating

As they are low in Copper, the ores have to be first concentrated through the froth-floatation process; only then could the copper extraction process begin. Froth floatation is usually used for sulphide ores because of their heavy nature.

Roasting

The already concentrated ore is boiled in the furnace called a reverberatory furnace with a lot of air. If there is any moisture during the hearing, it is removed, the unstable contamination is separated, and other contaminants are also isolated as moving oxides. Further, the Chalcopyrite is transformed (partly) into copper sulfides. This is the second step in the process of extraction of copper. Note that some ores of copper only go through partial roasting and don’t convert to their oxide.

Smelting

The heated ore is mingled with coke (powdered) and sand and is reheated in a furnace. This furnace is built of steel plates with the lining of clay bricks. As a consequence of smelting, two different layers of molten are created at the base of the steel furnace. The top layer contains slag and is isolated as trash, with the bottom layer referred to as matte. It contains cuprous sulfide and unaffected ferrous sulfide. This is the third step in the process of extraction of copper.  This step is used for the reduction of the ore.

Bessemerisation

The matte is transported to a Bessemer converter. This converter is built on a horizontal line and is fixed with little pipes known as tuyeres by which a gust of warm air and thin sand islet passed. A small amount of cuprous sulfide is changed into cuprous oxide through oxidation, and this then reacts with a lot more cuprous sulfide to result in Copper as a metal. This metal, however, is impure, but just 2% for 98% of it is pure and is commonly referred to as blister copper. This is the fourth step in the process of extraction of copper.  This process is also called self-reduction of copper as it doesn’t use any other external reducing agent.

Refining

The remaining 2% of contamination is refined with the help of electrolytic refining, which filters the blister copper to give us the purest of Copper. In electrolytic refining, the impure copper metal block is an anode with pure copper metal’s thin plate as a cathode, and sulphuric acid along with copper sulfate solution is acidified to act as an electrolyte. When the solution passes a final electric current, filtered Copper is settled on the cathode, and the dirt deposits around the anode in the state of sludge known as anode mud. This is the last step in the copper extraction process. 

Conclusion

The process used for the extraction of Copper relies on the state of the ore. Sulfide ores use the copper extraction process that isn’t the same as sulfate ores. Chalcopyrite (also known as copper pyrite) and other sulfide ores are the most popular ores used in the copper extraction process. There is a requirement for the concentration of ores with a low percentage of Copper before they can be refined for the final extraction of Copper. Extraction of Copper is generally through the self-reduction method. Economic leaching is allowed through new and modern methods of extraction of Copper. New techniques exist to make the copper extraction process easier and more efficient from various ores of copper, especially copper extraction from cuprous oxide.