Iranian Journal of Chemistry & Chemical Engineering (Dec 2007)
Liquid-Liquid Extraction of Gallium from Jajarm Bayer Process Liquor Using Kelex 100
Abstract
The solvent extraction of gallium from a concentrated Jajarm Bayer process liquor containing 164.90 g/l of Na2O, 86.70 g/l of Al2O3 and 106.02 ppm of gallium was investigated using 10 vol.% Kelex100, a 7-alkyl substituted-8 hydroxyquinoline as an extractant, 10 vol.% etanol as a modifier and kerosene as a diluent. At (Vo :Va = 1.0:1.0) organic to aqueous phase ratio and at room temperature, 93.39% of gallium was recovered in 60 minutes. Back extraction studies of the loaded organic phase were carried out using hydrochloric acid, sulfuric acid and sodium hydroxide. Scrubbing of aluminium co-extracted into the organic phase was carried out with 5.0 M HCl and subsequently stripping of gallium was carried out with 1.5 M HCl. The final strip liquor was found to contain 490 ppm of gallium along with 141.73 ppm of aluminium.