Aluminum
Aluminum is the third most abundant element in the earth's crust, accounting for 8% of the planet's soil and rocks (oxygen and silicon make up 47 percent and 28 percent , respectively). Aluminum is only found in nature in chemical compounds with other elements such as sulphur, silicon, and oxygen. Only aluminium oxide ore can be economically used to produce pure, metallic aluminium.
Metallic aluminium has a number of properties that make it useful in a variety of applications. It is nonmagnetic, lightweight, and nontoxic. It conducts heat and electricity while also reflecting light and heat. It is strong but malleable, and it retains its strength in cold temperatures without becoming brittle. Aluminum's surface oxidises quickly, forming an imperceptible barrier to corrosion. Furthermore, aluminium can be recycled easily and cheaply into new products.
Background
For thousands of years, aluminium compounds have proven to be useful. Persian potters created their strongest vessels around 5000 B.C. out of clay containing aluminium oxide. Aluminum compounds were used by the ancient Egyptians and Babylonians in fabric dyes, cosmetics, and medicines. However, aluminium was not identified as an element and isolated as a pure metal until the early nineteenth century. The difficulty of extracting aluminium from its natural compounds kept the metal rare for many years; it was still as rare and valuable as silver half a century after its discovery.
In 1886, two 22-year-old scientists independently developed a smelting process that allowed for the cost-effective mass production of aluminium. The Hall-Heroult process, named after its American and French inventors, is still the primary method of producing aluminium today. The Bayer process for refining aluminium ore, developed by an Austrian chemist in 1888, also made a significant contribution to the economical mass production of aluminium.
In 1884, the United States produced 125 lb (60 kg) of aluminium, which sold for about the same unit price as silver. In 1995, US plants produced 7.8 billion lb (3.6 million metric tonnes) of aluminium, while the price of silver was 75 times that of aluminium.
Materials for Production
Aluminum compounds are found in all types of clay, but bauxite is the most useful ore for producing pure aluminium. Bauxite is composed of 45-60% aluminium oxide and other impurities such as sand, iron, and other metals. Although some bauxite deposits are hard rock, the majority are relatively soft dirt that can be easily extracted from open-pit mines. Australia produces more than one-third of the world's bauxite supply. 1 lb (0.5 kg) of aluminium metal requires approximately 4 lb (2 kg) of bauxite. KMC aluminium Company is best aluminium extrusion profiles manufacturers in India.
To separate the aluminium compounds found in bauxite from the impurities, caustic soda (sodium hydroxide) is used to dissolve them. Small amounts of other chemicals may be used in the extraction depending on the composition of the bauxite ore.
Aluminum is produced in two stages: the Bayer process, which involves refining bauxite ore to produce aluminium oxide, and the Hall-Heroult process, which involves smelting the aluminium oxide to produce pure aluminium.
made of aluminium Some examples include starch, lime, and sodium sulphide.
The electrolyte (current-conducting medium) in the smelting process is cryolite, a chemical compound composed of sodium, aluminium, and fluorine. Cryolite was once mined naturally in Greenland, but the compound is now synthesised for use in the production of aluminium. To lower the melting point of the electrolyte solution, aluminium fluoride is added.
Carbon is another important component in the smelting process. Carbon electrodes conduct electricity through the electrolyte. Some of the carbon is consumed during the smelting process as it combines with oxygen to form carbon dioxide. In fact, for every pound (2.2 kg) of aluminium produced, approximately half a pound (0.2 kg) of carbon is used. Some of the carbon used in aluminium smelting comes from oil refining, while the rest comes from coal.
Aluminum smelting necessitates a large amount of electrical energy because it involves passing an electric current through a molten electrolyte. On average, it takes 15 kilowatt-hours (kWh) to produce 2 lb (1 kg) of aluminium. Electricity costs roughly one-third of the cost of smelting aluminium.
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