copper in the Earth's crust occurs as oxygen and sulfur compounds, it is characterized by deposits of hydrothermal origin.Copper ions are involved in many physiological processes of living organisms, such as human blood contains about 0.001 mg / g of copper.
found over 250 copper minerals, the most important of these are: chalcopyrite, covellite, chalcocite, bornite, cuprite, malachite and chrysocolla.Native copper is rare.Ores share of mineralogical composition on the oxide, sulphide and mixed.Distinguish them by structural features - are solid copper ore (polymetallic, copper-nickel and pyrite) or stringer-disseminated (slates and copper sandstones).
Copper has a face-centered cubic lattice.It is soft and malleable meta
l.It has a low reactivity.At room temperature and in dry air copper hardly oxidized, but when heated begins to fade due to the formation of oxide films.Its interaction with oxygen in the air becomes noticeable at about 200 ° C.
Even at high temperatures on the copper reacts with the nitrogen, carbon and hydrogen, but it readily combines with halogens.Wet chlorine begins to interact with it at ordinary temperature, thereby forming a copper chloride which is soluble in water.
Copper exhibits a special affinity for selenium and sulfur.These pairs it burns.Hydrogen and other combustible gases affect ingots of copper at high temperatures to form water vapor and carbon dioxide.They are distinguished from the copper, causing the appearance of cracks, which greatly impairs its mechanical properties.
for copper ores characterized by low copper content, therefore, to enrich their melting, separating the valuable minerals from the waste rock.About 80% of the copper is removed from the concentrate by pyrometallurgical methods.The melting was carried out in a reverberatory furnace, burning a carbonaceous fuel in the gas space above the bath surface.Hydrometallurgical methods of producing copper based on selective dissolution of minerals containing copper, in the solutions of ammonia and sulfuric acid.
Copper has a number of valuable properties for the technique: ductility, high electrical and thermal conductivity.It is the basic material for the production of wire, more than half the copper produced is used in the electrical industry.High corrosion resistance allows to create out of it parts of vacuum machines, refrigerators and heat exchangers.
- HiMiK.ru, Copper