Aluminium Concentrate
Aluminum manufacture is accomplished in two phases: the Bayer process of refining the bauxite ore to obtain aluminum oxide, and the Hall-Heroult process of smelting the aluminum oxide to release pure aluminum. The bauxite is purified by the Bayer Process. First the ore is mixed with a hot concentrated solution of sodium hydroxide. The NaOH will dissolve the oxides of aluminum and silicon but no other impurities such as iron oxides, which remains insoluble. The insoluble materials are removed by filtration. Preparation of aluminum concentrate typically involves the removal of water from an aluminum solution.
Aluminum manufacture is accomplished in two phases: the Bayer process of refining the bauxite ore to obtain aluminum oxide, and the Hall-Heroult process of smelting the aluminum oxide to release pure aluminum. The bauxite is purified by the Bayer Process. First the ore is mixed with a hot concentrated solution of sodium hydroxide. The NaOH will dissolve the oxides of aluminum and silicon but no other impurities such as iron oxides, which remains insoluble. The insoluble materials are removed by filtration. Preparation of aluminum concentrate typically involves the removal of water from an aluminum solution.
Properties of Aluminium Concentrate
| Molecular Weight | 26.98 |
|---|---|
| Appearance | Silvery |
| Boiling point | 2467 °C |
| Melting point | 660.37 °C |
| Density | 2700 kg/m3 |
| Electrical Resistivity | 2.6548 microhm-cm @ 0 °C |
| Electronegativity | 1.5 Paulings |
| Heat of fusion | 2.55 Cal/gm mole |
| Heat of vaporization | 67.9 K-Cal/gm at om at 765 °C |
| Poisson's ratio | 0.35 |
| Specific heat | 0.215 Cal/g/ K @ 25 °C |
| Thermal conductivity | 0.215 Cal/g/ K @ 25 °C |
| Thermal expansion | (25 °C) 23.1 µm·m-1·K-1 |
| Vickers hardness | 167 MPa |
| Young's modulus | 70 GPa |