Copper ore. The Epoch in the History of Humanity

One of the first metals with which man learned to work was copper, or in Latin Cuprum (Cu). It is simply impossible to exaggerate its role in the development of human civilization: an entire epoch in history was called the "Bronze Age" (bronze is an alloy of tin and copper). To receive this beautiful and malleable metal (the color of copper - golden-pink) learned before our era. The words "bornite", "chalcopyrite", "chalcosine", "kovelin", "enargite", "cuprite" sound like the names of something unusual, although in fact some of the ore-bearing ores are called so. The source of this metal was copper ore.

In nature Cuprum can be both in the form of nuggets, and the form of connections. There are several different types of copper ores that can be divided into sulphide, oxidized and mixed in composition. Usually, copper ore is complex, many other elements and compounds are present in it - sulfides of lead, zinc, nickel and other elements. In addition, it contains scattered elements - selenium, tellurium, cadmium, indium and the like. At cost, these metals are at least 50% of the Cuprum, extracted from the breed.

The most commonly used sulphide ores, which include compounds of Cu and sulfur. The very production of copper consists of several independent stages. The main way to get it is pyrometallurgical.

Usually, copper ore contains a small amount of Cuprum, so the rock is preliminarily enriched. To do this, it is crushed, mixed with water and some special substances, and then placed in a flotation machine. There all this is mixed, the particles of sulphides rise to the surface in the form of foam and are carried away, and the empty rock settles to the bottom.

The next stage of processing, which passes the copper ore, is called "smelting on matte." Sand is added to the resulting concentrate and the mixture is heated to the melting point of the metal. With this action, the sulfur is oxidized to sulfur oxide, and the molten metal is collected at the bottom of the furnace. This melt is poured into the converter and purged with air. As a result, the oxidation of sulfur produces metallic copper, which is poured into molds. When cooling such ingots (in them the content of Cu reaches 98%), sulfur dioxide is released. It is captured and then used as raw material for the production of sulfuric acid.

In order to obtain the metal of the required purity, the black copper must be refined. It can be of two types - fire or electrolytic. When refining, it is also possible to obtain the noble metals contained in the resulting blister copper.

Fire refining is carried out in special furnaces, electrolysis is carried out in baths lined with lead or viniplast.

For fire refining, the resulting preform is loaded into the furnace and melted. Then the air is blown through the liquid metal. During oxidation, a part of the impurities passes into the slag, while the other is sublimated and carried away with the furnace gases. Oxidized also Cuprum. All noble metals remain in the melt. The reduction of oxidized copper occurs when it interacts with carbon, the source of which is gas, a vapor-oil mixture, etc. This operation has been called copper-plating. Moreover, Cu is reduced by the carbon of wood. Then there is casting into ingots or special anode slabs for electrolysis refining.

Electrolysis refining is used when copper is intended for use in the electrical industry, or when it contains a large number of precious metals (silver, gold, platinum).

During electrolysis, the bath is filled with an electrolyte, the refined copper is placed in it as an anode, and pure cathode is used as the cathode, and a current is passed through the bath. As a result, pure metal precipitates on the cathode (purity - up to 99.95%).