"Minerals in Pakistan"
"Aluminum"
Aluminum forms strong chemical bonds with oxygen. Compared to most other metals, it is difficult to extract from ore, such as bauxite, due to the energy required to reduce aluminium oxide (Al2O3). For example, direct reduction with carbon, as is used to produce iron, is not chemically possible because aluminium is a stronger reducing agent than carbon. Indirect carbothermic reduction can be carried out using carbon and Al2O3, which forms an intermediate Al4C3 and this can further yield aluminium metal at a temperature of 1900–2000 °C. This process is still under development; it requires less energy and yields less CO2 than the Hall-Héroult process, the major industrial process for aluminium extraction. Because of the high melting point of aluminium oxide (about 2,000 °C (3,600 °F)) the pure metal is extracted by electrolysis.
Uses of Minerals:
Transportation:
Chromite:
Chromite is an iron chromium oxide FeCr2O4. It is an oxide belonging to the spinel group. Magnesium can substitute for iron in variable amounts as it forms a solid solution with magnesiochromite (MgCr2O4); substitution of aluminium occurs leading to hyrcenite (FeAl2O4).
Uses:
Most of the time, economic geology names chromite the whole chromite-magnesiochromite series: FeCr2O4, (Fe,Mg)Cr2O4, (Mg,Fe)Cr2O4 and MgCr2O4.The two main products of chromite refining are ferrochromium and metallic chromium, for those products the ore smelter process differs considerably. For the production of ferrochromium the chromite ore (FeCr2O4) is reduced with either aluminium or silicon in a aluminothermic and reaction for the production of pure chromium the iron has to be separated from the chromium in a two step roasting and leaching process.
Chromite is also used as a refractory material, because it has a high heat stability.
Coal:
Copper:
Gold:"
Iron:
Zink:"
"Aluminum"
Aluminum forms strong chemical bonds with oxygen. Compared to most other metals, it is difficult to extract from ore, such as bauxite, due to the energy required to reduce aluminium oxide (Al2O3). For example, direct reduction with carbon, as is used to produce iron, is not chemically possible because aluminium is a stronger reducing agent than carbon. Indirect carbothermic reduction can be carried out using carbon and Al2O3, which forms an intermediate Al4C3 and this can further yield aluminium metal at a temperature of 1900–2000 °C. This process is still under development; it requires less energy and yields less CO2 than the Hall-Héroult process, the major industrial process for aluminium extraction. Because of the high melting point of aluminium oxide (about 2,000 °C (3,600 °F)) the pure metal is extracted by electrolysis.
Uses of Minerals:
Transportation:
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| Household Aluminium Foil |
Chromite is an iron chromium oxide FeCr2O4. It is an oxide belonging to the spinel group. Magnesium can substitute for iron in variable amounts as it forms a solid solution with magnesiochromite (MgCr2O4); substitution of aluminium occurs leading to hyrcenite (FeAl2O4).
Uses:
Most of the time, economic geology names chromite the whole chromite-magnesiochromite series: FeCr2O4, (Fe,Mg)Cr2O4, (Mg,Fe)Cr2O4 and MgCr2O4.The two main products of chromite refining are ferrochromium and metallic chromium, for those products the ore smelter process differs considerably. For the production of ferrochromium the chromite ore (FeCr2O4) is reduced with either aluminium or silicon in a aluminothermic and reaction for the production of pure chromium the iron has to be separated from the chromium in a two step roasting and leaching process.
Chromite is also used as a refractory material, because it has a high heat stability.
Coal:
Copper:
Gold:"
Iron:
Zink:"
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