عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Uranium (VI) solvent extraction from the acidic sulfate solutions by Alamine 336 diluted in kerosene has been investigated. The effect of the contact time between phases, sulfuric acid concentration, extractant concentration, uranium concentration, organic/aqueous phase ratio, and temperature were studied. The results demonstrated that the uranium extraction was a fast, exothermic, and spontaneous reaction. Log Kex is calculated to be 5.94. The process parametric variation studies indicated a strong influence of sulfuric acid concentration on the extraction percentage of uranium. The extraction percentage was increased with an increase in the extractant concentration as well as the organic/aqueous phase ratio and decreased with an increase in the uranium concentration. Using
0.05 mol L-1 Alamine 336˚C at 25˚C with organic/aqueous phase ratio of 1:1, an extraction percentage of about 99.72% was achieved when the H2SO4 concentration was 0.15 mol L-1. The uranium extraction from the leach liquor solution was done under these optimum conditions, and iron (ІІІ) removal has investigated. Uranium stripping from the loaded solvent was carried out by many salt and acid solutions in the four steps. The effect of temperature was studied, and for the first time in this study, the enthalpy change of stripping reaction by using various chemical agents was obtained. 99.87% of uranium loaded in the organic phase was removed by 0.5 mol L-1 (NH4)2CO3 in a single stripping step.