کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
213572 | 462110 | 2007 | 10 صفحه PDF | دانلود رایگان |
Iron(III) can be used as an oxidant in the leaching of uranium ore in an acid medium. The oxidation of iron(II) to iron(III) using an SO2/O2 gas mixture was investigated in order to provide an iron(III) stream for uranium extraction. The effects of pH, temperature and SO2/O2 volumetric ratios were considered. Oxidation of iron(II) by SO2/O2 was controlled by diffusion of SO2 or O2 at pH 2 and 40 °C. However as the pH decreased below pH 1, the reaction was controlled by a slow chemical step and the reaction rate decreased. Increasing the temperature increased the oxidation rate at pH 0.8, and at 70 °C the rate again became dependent on SO2 or O2 diffusion. The oxygen efficiency for a fixed reactor set-up was dependent on the SO2/O2 ratio and total flow rate of the gas. In leach tests, the uranium extraction achieved with iron(III) solution prepared by SO2/O2 oxidation was the same as that for a standard uranium leach with conventional oxidant.
Journal: Hydrometallurgy - Volume 85, Issues 2–4, March 2007, Pages 183–192