WHAT IS ALUMINIUM?
Aluminium is a chemical element in the boron group with symbol Al and atomic number 13. It is a silvery white, soft, ductile metal. Aluminium is the third most abundant element, and the most abundant metal, in the Earth's crust.
Symbol: Al
Melting point: 1,221°F (660.3°C)
Electron configuration: [Ne] 3s2 3p1
Discovered: 1825
Atomic mass: 26.981539 ± 0.0000008 u
Discoverer: Hans Christian Ørsted
Properties:
-Silvery-white solid metal
-Nontoxic (as the metal)
-Nonmagnetic
- Light weight
- Easily formed, machined, and cast
- Good thermal and electrical conductor
- Resistance to corrosion
- High reflectance in finely powdered form
Mode of extraction
Aluminum is the most abundant metallic element in the Earth's crust. It is almost never found in its elemental state due to the strong reaction with oxygen; instead it is found in oxides or silicates.
The first step to get aluminum from the Earth’s crust is mining. The aluminum ores are mixed with sodium hydroxide that helps dissolve the oxides of the aluminum and silicon. Other impurities are removed through the filtration and boiling which result purified aluminum oxides.
Using the Hall-Heroult Method by mixing aluminum oxides with cryolite, the mixture will be melted and electrolyzed with large current. Then, aluminum ions are reduced to form aluminum metal.
Uses for Alumnium
n The most common use of aluminum is in packaging such as drink cans, foil wrapping, bottle tops and foil containers. Because of its resistance of corrosion, non-scent, non-toxic and tasteless, aluminum is trusted and widely used in food and beverage industries.
n Aluminum is also used in transportation. Its strength when comparing to its weight makes aluminum popular in transportation industries. Less weight of the vehicle means less force and energy to make them move. Especially for aircrafts, aluminum saves many weights.
n The electrical conductivity property of aluminum is perfect for electric power lines. It can conduct high electricity with lighter weight than copper. Also, aluminum is cheap and resistance to corrosion which makes it a great choice for long-distance electric distribution.
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One World Links
1. Environmental issues
Creating aluminum from raw materials has a shocking impact on the environment. Up to six tons of bauxite ore are needed to produce one ton of aluminum metal. The mining process can cause the local erosion and deforestation, water and air pollution and ecosystem disruption.
2. Health issues
There are several concerns on using aluminium with food and beverage products. People are worried about the toxic which could cause when food contacts with aluminium package. Also, the rumors which claim that aluminium might cause Alzheimer’s disease. However, it has been announced from the U.S. Food and Drug Administration that metallic aluminium as Generally Recognized as Safe (GRAS). Many researches from the Association conclude that:
Aluminum is not linked to Alzheimer’s disease.
Alzheimer’s disease prior to old age.
Aluminum is poorly absorbed by the body.
The dietary intake of aluminum from food packaging is far too small to be toxic.