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Cobalt ore. Cobalt extraction refers to the techniques used to extract cobalt from its ores and other compound ores. Several methods exist for the separation of cobalt from copper and nickel. They depend on the concentration of cobalt and the exact composition of the ore used.
Roasting is a process of heating a sulfide ore to a high temperature in the presence of air. It is a step in the processing of certain ores . More specifically, roasting is often a metallurgical process involving gas–solid reactions at elevated temperatures with the goal of purifying the metal component(s).
The solid product from roasting is often called "calcine". In oxidizing roasting, if the temperature and gas conditions are such that the sulfide feed is completely oxidized, the process is known as "dead roasting". Sometimes, as in the case of pre-treating reverberatory or electric smelting furnace feed, the roasting process is performed with ...
For sulfide ores, a different process is taken for beneficiation. The ore needs to have the sulfur removed before smelting can begin. Roasting is the primary method of separating, where wood was placed on heaps of ore and set on fire to help with oxidation. [6] [7] 2 Cu 2 S + 3 O 2 → 2 Cu 2 O + 2 SO 2
Roasting the carbonate and sulfide minerals in the air converts them to oxides. The oxides, in turn, are smelted into the metal. Carbon monoxide was (and is) the reducing agent of choice for smelting. It is easily produced during the heating process, and as a gas comes into intimate contact with the ore.
Cobalt is also used in the petroleum industry as a catalyst when refining crude oil. This is to purge it of sulfur, which is very polluting when burned and causes acid rain. [11] Cobalt is the active center of a group of coenzymes called cobalamins. Vitamin B 12, the best-known example of the type, is an essential vitamin for all animals.
Maggots hatch, making their way through the paste, digesting proteins in the process, and transforming the product into a soft creamy cheese. Then the cheesemonger cracks open the top – which is ...
Chalcanthum – the residue produced by strongly roasting blue vitriol (copper sulfate); it is composed mostly of cupric oxide. Chalk – a rock composed of porous biogenic calcium carbonate. CaCO 3; Chrome green – chromic oxide and cobalt oxide. Chrome orange – chrome yellow and chrome red. Chrome red – basic lead chromate – PbCrO 4 +PbO