Albite | Allophane | Alunite | Amblygonite | Amorphous Silica | Anatase | Andalusite | Anorthite | Anorthosite | Aplite | Aragonite | Asbestos | Attapulgite, Palygorskite | Azurite | Baddeleyite | Ball Clay | Barytes, Barite | Bastnäsite | | Berthierite | Beryl | Biotite | Boracite | Borate Minerals | Bornite | Brookite | Brucite | Calcite | Cassiterite | Celsian | Cerussite | Chalcedony | Chlorite | Chrysotile | Corundum | Dickite | Dolomitic Limestone, Dolostone | Fayalite | Feldspar | Galena | Gibbsite | Granite | Gypsum, Calcium sulphate | Hübnerite | Halloysite | Hectorite | Hematite | Hydroboracite | Illite | Illmenite | Iron Pyrite | K-Feldspar | Kaolinite | Kernite | Kyanite | Laterite | Lepidolite | Leucite | Limestone, Calcium Carbonate | Limonite | Magnesite | Magnetite | Malachite | Manganite | Mica | Microcline, Anorthoclase | Monazite | Montmorillonite, Bentonite | Mullite | Muscovite | Na-Feldspar | Nacrite | Nepheline | Nontronite | Oligoclase | Olivine | Organics | Pegmatite | Phlogopite Mica | Plagioclase | Potash Mica | Pyrophyllite | Quartz | Quartzite | Rutile | Sanidine | Saponite | Selenite | Sepiolite | Sericite | Serpentine | Shale | Sillimanite | Slate | Smectite | Soda Mica | Sodalite | Sphalerite | Steatite | Stibnite | Sylvite | Talc | Tremolite | Trona | Vanadinite | Willemite | Witherite | Zeolite

Bauxite

The main ore from which alumina oxide products are refined, contains diaspore, gibbsite and boehmite minerals. LOI is 25%.

The Bayer refining process of turning Bauxite into alumina used by alumina refineries worldwide involves four steps - grinding and digestion, clarification, precipitation and calcination. Alcoa describes the process like this:

"To turn bauxite into alumina, we grind the ore and mix it with lime and caustic soda, pump this mix into high-pressure containers, and heat it. The aluminum oxide is dissolved by the caustic soda, then precipitated out of this solution, washed, and heated to drive off water. What is left is the white powder called alumina, which is transformed into aluminum metal in the smelting process."

Related Information

Links

URLs http://en.wikipedia.org/wiki/Bauxite
Bauxite at Wikipedia
URLs http://www.minersoc.org/pages/gallery/claypix/gibbsite/gibbsite.html
Micrograph of gibbsite at minersoc.org
Materials Alumina Hydrate
Materials Alumina

By Tony Hansen


Tell Us How to Improve This Page

Version: Oct/2020

Or ask a question and we will alter this page to better answer it.

Email Address

Name

Subject

Message


Upload picture

Please check recaptcha to proceed


Copyright 2008, 2015, 2017 https://digitalfire.com, All Rights Reserved