Department of Mining and Metallurgical Engineering, Yazd University, Yazd, Iran
Gallium extraction from Jajarm Bayer process liquor (Jajarm, Iran) was investigated using microemulsions. Also the behavior of aluminum was studied as an impurity. Kelex100 (4-ethyl, 1-methyl, 7-octyl, 8-hydroxyquinoleine), iso-decanol and n-butanol, and kerosene were used as the surfactant, co-surfactant, and oil phase, respectively. Ternary phase diagrams were produced using various co-surfactants at different C/S ratios. The results obtained show that Winsor II is the predominant region, and the least area was obtained using iso-decanol at C/S = 4. Using n-butanol or iso-decanol at C/S = 2, 100% of gallium was extracted. The equations of the statistical models for the gallium and aluminum extractions using different co-surfactants were calculated. While the highest gallium extraction (100%) was obtained using n-butanol, due to the high co-extraction of aluminum, the lowest separation and enrichment factors were obtained for this system. The highest separation and enrichment factors were obtained using iso-decanol at C/S = 2. The point with the compositions of XAF = 30, XOF = 20, and XC/S = 50 was found to be a suitable choice, and led to 74% and 14% extractions for gallium and aluminum, respectively. An enrichment factor of 5.28 was obtained.