magnéziumérc

Magnéziumérc refers to naturally occurring rocks or minerals from which magnesium can be economically extracted. The most important magnesium-containing minerals are dolomite and magnesite. Dolomite is a double carbonate of calcium and magnesium, with the chemical formula CaMg(CO3)2. Magnesite is a carbonate of magnesium, with the formula MgCO3. Other magnesium-containing minerals like olivine and serpentine can also be sources of magnesium, although they are often less commercially significant due to processing challenges.

The extraction of magnesium from these ores typically involves a series of chemical and thermal processes. For magnesite, calcination (heating) drives off carbon dioxide, producing magnesium oxide (MgO), also known as magnesia. This magnesia can then be further processed, often through electrolysis or a Pidgeon process involving ferrosilicon, to produce metallic magnesium. Dolomite also undergoes calcination to produce a mixture of calcium oxide and magnesium oxide. Separating the magnesium oxide from the calcium oxide is a key step in recovering magnesium from dolomite.

Magnesium is a lightweight and strong metal, making it valuable in alloys, particularly with aluminum, for use in the automotive, aerospace, and electronics industries. Magnesium compounds derived from these ores have numerous applications, including in refractories, cement production, fertilizers, and pharmaceuticals. The primary producing regions for magnesium ores are China, Russia, the United States, and Austria. The economic viability of mining magnesium ore depends on the concentration of magnesium in the deposit and the proximity to processing facilities and markets.

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