Chrome ore

English name:

the Chrome Mine,
Chinese chrome ore resource-poor to meet the needs of the degree to see is a shortage of resources. The total reserves of 10.78 million tons of ore, which accounted for 53.6 percent of high-grade ore. Chrome mineral deposits, 56, distributed in Tibet, Xinjiang, Inner Mongolia, Gansu, and other 13 provinces (autonomous regions), Tibet is the most important, to maintain reserves accounted for about half of the country. China chromium deposit is typical of ultrabasic rocks magma-type deposits, the vast majority are ophiolite type deposits occur in the ophiolite belt. Tibet Luobusha chrome ore and the Xinjiang Saertuohai chrome ore h ave such a case. From the metallogenic epoch, China chrome ore formation era Mesozoic and Cenozoic.
In the metallurgical industry, chromite is mainly used in the production of ferrochrome and chromium. The production of ferrochrome steel material to add a variety of high-strength, corrosion resistance, wear resistance, high temperature, oxidation-resistant special steel such as stainless steel, acid resistant steel, heat resistant steel, ball bearing steel, spring steel, tool steel and so on. Chromium is mainly used for smelting cobalt, nickel, tungsten and other elements of special alloys. Special steel and special alloy is the aviation, aerospace, automotive, shipbuilding, and defense industry production guns, missiles, rockets, ships and other essential material.
In refractories, chromite is used to manufacture chrome brick, chrome magnesia brick and other refractories.
Chromite is mainly used in the chemical industry, the production of sodium dichromate, and then preparation of other chromium compounds, used in paint, textile, electroplating, tanning industries, but also production of catalysts and catalyst agent.
Chromite is a shortage of minerals reserves, low production, rely on imports for more than 80% of annual consumption.
Chromium affinity for oxygen and pro-iron, a stronger affinity for oxygen, and only show affinity to sulfur reduction and sulfur fugacity higher. Endogenous role under the conditions of chromium generally showed the trivalent. Six acid Cr3 + and of Al3 + Fe3 + ionic radius close to, so they can be submitted to a wide range of isomorphous. In addition, with chrome-class quality and the like instead of the elements there of Mn and Mg, Ni, Co., Zn, magnesium iron silicate minerals and minerals chromium is widely distributed. Supergene with strong oxidative conditions (alkaline medium) of Cr3 + oxidation of Cr6 + in the form of chromate ions, chromium ions into inactive soluble chromium anions migrate. Case of highly polarized nature of the ion (eg Cu, Pb, etc.), the formation of insoluble chromate minerals.
In nature has been found that chromium-containing minerals are about more than 50 species belonging to the oxide, chromate and silicate. There is also a small number of hydroxide, iodate, nitrides and sulfides. Chromium nitride and chromium sulfide minerals found only in meteorites.
Chrome minerals of commercial value are chrome spinel minerals, their chemical formula of (Mg, Fe2 +) (Cr World pipe network reported that the world's steel pipe network to provide the world's steel pipe network editor , Al and Fe3 +) 2O4 or (Mg, Fe2 +) O (Cr, Al and Fe3 + ) 2O3, Cr2O3 content 18% to 62%.
Industrial value of chromium minerals, and its content of Cr2O3 are generally located in more than 30%, which is common:
1. The chromite
chemical composition (Mg, Fe) Cr2O4 between ferrous between chromite (FeCr2O4, an containing FeO32.09%, of Cr2O3 67.91) and magnesium chromite (MgCr2O4, including MgO20 World pipe network reported that the world's steel pipe network to provide the world's steel pipe network editor .96% of Cr2O3 79.04%), someone will usually ferrous chromite and magnesium chromite are also referred to as chromite. Chromite crystal axis, the crystal was small octahedral, usually in granular and compact massive aggregates, color black, streak brown, semi-metallic luster, hardness 5.5, specific gravity of 4.2 to 4.8 with weakly magnetic. Chromite is the minerals of magmatic origin, produced in the ultrabasic rocks, when the ore-bearing rocks subjected to weathering damage, chromite often transferred placers. Chromite is the most important mineral raw materials for refining chromium, low-quality iron-rich ore can be used for advanced refractory.
2. The spar
of chromium-rich class, also known as the ferrochrome spinel or aluminum chromite. The chemical composition of Fe (Cr, Al) 2O4, including of Cr2O3 32% to 38%. Their morphology, physical properties, causes, occurrence, and the same purpose and chromite. The
3. Hard chrome spinel
chemical composition (Mg, Fe) (Cr, Al) 2O4, including of Cr2O3 32% to 50%. Their morphology, physical properties, causes, occurrence and uses of chromite.