Reaction of Bauxite with Hydrochloric Acid Under Autoclave Conditions

Studies are made of the use of hydrochloric acid for the autoclave decomposition of boehmite-kaolinite bauxites from the North Onezhky Deposit. The spatial location and structure of the bauxites are investigated, and the solid residue left after autoclave decomposition is examined by x-ray phase analysis and electron microscopy to study the mechanism of the bauxites’ dissolution. The data that is obtained confirms the presence of hard films of amorphous silica. These films prevent complete dissolution of the aluminum-bearing minerals: boehmite and kaolinite.