Aluminium is a chemical element grouped under the boron group. It is also spelt as aluminium and its chemical symbol is Al while the atomic number is 13. Physical properties include silvery color, softness, and considerable ductility. Aluminium has high abundance in terms of the composition of the crust of the earth and it comes third after oxygen and silicon. Aluminum in NJ does not occur in its native form because it is highly reactive.
Under natural circumstances, the ore is found in combination with over 270 other minerals. The primary ore is bauxite. The most remarkable properties of the element are the low density and high resistance to corrosion. The low density is very important in making aircrafts and structural materials. Rusting is not a problem in this element making it very useful in many industries.
There are several ways of producing aluminium in NJ. The most used method is called the Hall-Heroult process. Other techniques include indirect carbothermic reduction and electrolytic smelting of alumina. Indirect carbothermic reduction has proved effective, but it is still under development. It consumes less power and generates less Carbon monoxide gas in comparison to Hall-Heroult process.
Hall-Heroult process involves dissolving alumina into molten cryolite with calcium fluoride. When aluminium dissolves in the electrolyte, it dissociates releasing its ions to move around freely. The resultant compound is then reduced electrolytically into aluminium. The reduction process takes place within the temperature range of 950 and 980 degrees Celsius. Aluminium ions are reduced allowing the metal to sink at the bottom of the compound. The Hall-Heroult process was a replacement for the Wohler process, which used potassium to reduce anhydrous aluminum chloride.
This method very energy inefficient, but its application cannot be dropped because it is the most ecological and economical. The metal is able to be recycled up to 100 hundred without losing its properties. Increased manufacture of beverage cans in late 60s gave recycling a lot of importance in NJ. When recycling, scrap is melted to form an ash-like substance called dross and the pure form of the metal. With further refinement dross can be converted into the substances too.
Recycled metal is called secondary aluminum although its properties and applications are the same as those of the primary form. To enhance mechanical properties of this metal, it is mostly used in form of an alloy with other materials. The alloys may comprise of silicon, zinc, manganese, copper, and magnesium. Major applications include manufacture of transport vessels like trucks, railway cars, aircrafts and marine vessels.
Other applications are in industries like packaging, construction, household items, lighting, engineering, insulation, electronics, and power distribution among others. Hydrogen gas can also be produced by reacting the metal with sodium hydroxide or hydrochloric acid. The powdered form is also an important additive in paints, thermite, and solid rocket fuels. Some countries issue currencies that are products of aluminium or its alloys.
Studies do not reveal any serious health concerns related with the element. However, if consumed in large amounts, it may cause neurotoxicity and other conditions. Some people are also allergic and may experience digestive disorders, contact dermatitis, and vomiting when they come in contact with it.
Under natural circumstances, the ore is found in combination with over 270 other minerals. The primary ore is bauxite. The most remarkable properties of the element are the low density and high resistance to corrosion. The low density is very important in making aircrafts and structural materials. Rusting is not a problem in this element making it very useful in many industries.
There are several ways of producing aluminium in NJ. The most used method is called the Hall-Heroult process. Other techniques include indirect carbothermic reduction and electrolytic smelting of alumina. Indirect carbothermic reduction has proved effective, but it is still under development. It consumes less power and generates less Carbon monoxide gas in comparison to Hall-Heroult process.
Hall-Heroult process involves dissolving alumina into molten cryolite with calcium fluoride. When aluminium dissolves in the electrolyte, it dissociates releasing its ions to move around freely. The resultant compound is then reduced electrolytically into aluminium. The reduction process takes place within the temperature range of 950 and 980 degrees Celsius. Aluminium ions are reduced allowing the metal to sink at the bottom of the compound. The Hall-Heroult process was a replacement for the Wohler process, which used potassium to reduce anhydrous aluminum chloride.
This method very energy inefficient, but its application cannot be dropped because it is the most ecological and economical. The metal is able to be recycled up to 100 hundred without losing its properties. Increased manufacture of beverage cans in late 60s gave recycling a lot of importance in NJ. When recycling, scrap is melted to form an ash-like substance called dross and the pure form of the metal. With further refinement dross can be converted into the substances too.
Recycled metal is called secondary aluminum although its properties and applications are the same as those of the primary form. To enhance mechanical properties of this metal, it is mostly used in form of an alloy with other materials. The alloys may comprise of silicon, zinc, manganese, copper, and magnesium. Major applications include manufacture of transport vessels like trucks, railway cars, aircrafts and marine vessels.
Other applications are in industries like packaging, construction, household items, lighting, engineering, insulation, electronics, and power distribution among others. Hydrogen gas can also be produced by reacting the metal with sodium hydroxide or hydrochloric acid. The powdered form is also an important additive in paints, thermite, and solid rocket fuels. Some countries issue currencies that are products of aluminium or its alloys.
Studies do not reveal any serious health concerns related with the element. However, if consumed in large amounts, it may cause neurotoxicity and other conditions. Some people are also allergic and may experience digestive disorders, contact dermatitis, and vomiting when they come in contact with it.
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