Aluminum
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Aluminum is the most abundant metal in the Earth's crust. It was first extracted in small amounts in 1825 but commercial production only began in 1854. In the 1880s, Hall and Héroult independently invented an electrolytic process for extracting aluminum from aluminum oxide which greatly reduced its cost. This along with the Bayer process for extracting aluminum oxide from bauxite led to aluminum becoming widely used. Today, aluminum is highly recycled due to its light weight, durability, conductivity, workability and versatility in applications like transportation, packaging and construction.
Aluminum
- 1. ALUMINUM
- 2. The ancient Greeks and Romans used alum in medicine as an astringent, and in dyeing processes. In 1761 de Morveau proposed the name "alumine" for the base in alum. In 1807, Davy proposed the name alumium for the metal, undiscovered at that time, and later agreed to change it to aluminum. What’s in NAME?
- 3. Shortly thereafter, the name aluminium was adopted by IUPAC to conform with the "ium" ending of most elements. Aluminium is the IUPAC spelling and therefore the international standard. Aluminium was also the accepted spelling in the U.S.A. until 1925, at which time the American Chemical Society decided to revert back to aluminum, and to this day Americans still refer to aluminium as "aluminum". What’s in NAME?
- 4. What is Aluminum? • Aluminum is the most abundant metallic element in the Earth’s crust (about 8%) and is the third most common element after oxygen and silicon. Unlike copper or gold, aluminum cannot be found in nature in the pure state because of its high affinity with oxygen, being so always combined with another element like in alum (KAl(SO4)2∙12H2O) and in aluminum oxide (Al2O3).
- 5. 1787 – 1825 ; Scientists found unknown metal in alum but they did not have way how to extract it. Hans Christian Oersted, a Danish chemist, was the first to produce tiny amounts of aluminum in 1825 History of Aluminum
- 6. Two years later, Friedrich Wöhler, a German chemist, developed a different way to obtain aluminum. By 1845, he was able to produce samples large enough to determine some of aluminum's basic properties. History of Aluminum
- 7. Wöhler's method was improved in 1854 by Henri Étienne Sainte-Claire Deville, a French chemist. Deville's process allowed for the commercial production of aluminum. As a result, the price of aluminum dropped from around $1200 per kilogram in 1852 to around $40 per kilogram in 1859. Unfortunately, aluminum remained too expensive to be widely used. History of Aluminum
- 8. Two important developments in the 1880s greatly increased the availability of aluminum. History of Aluminum
- 9. The first was the invention of a new process for obtaining aluminum from aluminum oxide. Charles Martin Hall, an American chemist, and Paul L. T. Héroult, a French chemist, each invented this process independently in 1886. History of Aluminum
- 10. The second was the invention of a new process that could cheaply obtain aluminum oxide from bauxite. History of Aluminum
- 11. Bauxite is an ore that contains a large amount of aluminum hydroxide (Al2O3·3H2O), along with other compounds. History of Aluminum Karl Joseph Bayer, an Austrian chemist, developed this process in 1888. The Hall- Héroult and Bayer processes are still used today to produce nearly all of the world's aluminum.
- 12. In 1888, Hall formed the Pittsburgh Reduction Company, which is now known as the Aluminum Company of America, or Alcoa. When it opened, his company could produce about 25 kilograms of aluminum a day. By 1909, his company was producing about 41,000 kilograms of aluminum a day. As a result of this huge increase of supply, the price of aluminum fell rapidly to about $0.60 per kilogram.
- 13. Alcoa Inc. (from Aluminum Company of America) is the world's third largest producer of aluminum.
- 14. Bauxite, found in parts of the world where high temperatures are combined with heavy rainfall, is a mixture, produced by weathering, of chalk and rock containing aluminium hydroxide. It has the highest concentration of aluminium of the easily accessible compounds found in the Earth's crust, producing about one ton of metal from every four ton of ore. Production of Aluminum
- 17. The complex Bayer process uses high temperature and pressure to convert the crushed bauxite to pure aluminium hydroxide, which is then roasted to drive off the water and convert it to aluminium oxide, or calcined alumina, a white powder.
- 18. The next step is the electrolytic smelting process, where the alumina is mixed with a molten cryolite electrolyte in a pot lined with pitch and coke which acts as a cathode. A carbon anode is lowered to the surface of the mixture from above, and a heavy direct electrical current at 4-5 V is passed between anode and cathode. The Aluminium Smelting Process (Hall Heroult Process)
- 20. l. Lightness: On a volume basis, aluminum is only about one-third the weight of steel. Significant weight savings can be made in almost every type of mechanical application. Properties of Aluminum
- 21. • 2. Durability • Because aluminum quickly forms an impervious oxide skin on exposed surfaces, it is highly resistant to atmospheric corrosion, even in marine conditions. So it does not require painting for protection.
- 22. • 3. Conductivity • The specific electrical conductivity of aluminum makes it indispensable for electronics and electrics. Aluminum cables carry twice as much current as copper of the same weight. High thermal conductivity makes it very suitable for heating and cooling applications.
- 23. • Workability • Aluminium can be formed by all the common metal-working techniques, more easily than most. It is easy to cast, or die- cast to precise and complex shapes. It can be forged, rolled to a superfine foil, and extruded into intricate sections, or pressed. Superplastic alloys can be worked almost like vacuum-formed plastics. Aluminium is also one of the easiest and fastest materials to machine.
- 24. • 5. Versatility • Aluminium alloys can be stiff or supple, especially strong or particularly corrosion- resistant. It is easy to tailor the metal, by alloying and heat treatment, to meet a wide range of needs.
- 25. • 6. Attractiveness • Aluminium is a "clean" material. It looks good without further finishing, but takes kindly to a wide range of applied coatings, from paints to colored anodizing.
- 26. • 7. Recyclability • Aluminium is easily reprocessed using 5% of the energy needed for primary smelting: almost one third of all the aluminium used today is produced from scrap, either from production processes or from recycled products.
- 27. Presently, aluminum is the second largest used metal in the world, mainly due to its light weight, high strength and recyclability. Uses of Aluminum
- 28. • Aluminum Markets • Top markets for the industry are transportation, beverage cans and other packaging, and building/construction. • In 1994, transportation first emerged as the largest market for aluminum, at about one- quarter of the market, with passenger cars accounting for the vast majority of the growth. Up until 2009, that trend has largely continued.
- 29. • Transportation • While transportation has typically represented the largest market for aluminum in North America over the past two decades, 2009 marked the worst year for auto sales since 1982 and, as such, transportation applications accounted for only 23.7 percent of all aluminum shipments - 4.22 billion pounds in all.
- 31. • Packaging • In 2009, containers and packaging regained their position as the top market for aluminum. The aluminum industry shipped 4.73 billion pounds for packaging applications, or 26.5 percent of all shipments. Aluminum is used in products such as beverage cans and bottles, food containers, and household and institutional foil.
- 32. • Building and Construction • Largely due to products in the residential, industrial, commercial, farm, and highway sectors, the 2009 building and construction market accounted for 2.13 billion pounds of net shipments, good for 11.9 percent of total shipments and the third largest North American market for aluminum.
- 33. • Electrical • Aluminum has many advantages for electrical applications. It is lightweight, strong, corrosion resistant, and a highly efficient conductor (aluminum has twice the conductivity, per pound, of copper)— rendering it the material of choice for transmitting power from generating stations to homes and businesses.
- 34. • Use in Households • This metallic element is used for door knobs, window frames and kitchen utensils. The element is applied in kettles, saucepans, toasters and refrigerators. It is also used in indoor and outdoor furniture. Some sports equipment like golf clubs and tennis balls also use it.
- 35. Best thing about Aluminum • Aluminum Recycling • Aluminium's high scrap value encourages recycling, with the result that it is not a significant contributor to waste disposal problems because it can be collected before waste. One third of all aluminum comes from scrap, and as much as 70% of the metal used in electrical engineering, building and transport is re-used, often again and again.