Bayer process

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Bayer process,

procedure for obtaining alumina from the aluminum ore bauxite. The alumina can then be used for various industrial purposes or smelted to provide aluminum. The first step in the process is the mixing of ground bauxite into a solution of sodium hydroxide. By applying steam and pressure in tanks containing the mixture, the bauxite slowly dissolves. The alumina released reacts with the sodium hydroxide to form sodium aluminate. After the contents of the tank have passed through other vessels where the pressure and temperature are reduced and impurities are removed, the solution of sodium aluminate is placed in a special tank where the alumina is precipitated out. The precipitate is removed from the tank, washed, and heated in a kiln to drive off any water present. The residue is a commercially pure alumina.

Bayer process

[′bī·ər ‚präs·əs]
A method of producing alumina from bauxite by heating it in a sodium hydroxide solution.
References in periodicals archive ?
Billions of tonnes of this "red mud" sit in holding ponds around the world, an amount that will continue to increase as long as the Bayer process is used.
These include the formation of anionic polyacrylamide through hydrolysis, (17) the synthesis of sulfomethylated derivatives from the reaction of polyacrylamide with formaldehyde and sodium bisulfate, (18) the formation of aminomethylated polyacrylamide from the reaction of polyacrylamide with formaldehyde and dimethylamine (Mannich reaction), (19) and the generation of various derivatives by transamidation reactions including hydroxamated polyacrylamides used as a flocculant in the Bayer process.
The available alumina and reactive silica results quoted are unbeneficiated based on low temperature caustic digest analysis (143AC), to simulate extraction by the Bayer process.
Orbite ) and Veolia Environmental Services ( Veolia ) signed an exclusive worldwide collaborative agreement for the treatment and recycling of red mud generated by industrial alumina production using the Bayer process.
He explained the improved Bayer process step by step: identified a market problem, formed an economic value proposition and solicited feedback about the value proposition from parties throughout the value chain.
Orbite technologies enable environmentally-neutral extraction of smelter-grade alumina (SGA), high-purity alumina (HPA) and high-value elements, including rare earths and rare metals, from a variety of sources such as aluminous clay and bauxite, without generating the toxic red mud residue that the traditional Bayer process produces.
Stamixco LLC says the Bayer process also allows the mixers to be made and sold at lower cost.
The Bayer process uses caustic soda to digest the ore and solubulize the alumina from the bauxite as sodium aluminate.
The Bayer process mixes bauxite with caustic soda (otherwise known as lye) in high-pressure digesters at 300 to 480[degree]F.
Orbite s innovative and proprietary process can successfully produce alumina from clay and other feedstocks including red mud, the waste by-product of alumina production from bauxite using the industry-standard Bayer process.
In conjunction with the refinery scoping study that is currently underway, Bauxite Resources is reviewing all resources for amenability to higher temperature Bayer Process refining.

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