Uranium mixed oxide separation

摘要

A uranium mixed oxide separation process, in which iron-rich acidic uranium- and sulphate-containing mining water is treated with a strongly basic ion exchange resin without previous iron removal and uranium oxide precipitation with hydrogen peroxide, comprises eluting iron and uranium into separate fractions in columns at a pH of 1.8-7.0 and at an initial uranium concentration of /- 0.5 mg/l, using a fresh regenerate, which elutes the iron and then the uranium as separate fractions, and/or two different fresh regenerates, the first preferentially dissolving the iron fraction and the second dissolving both the iron and the uranium fractions. The fresh regenerate for iron elution consists of 0.05-0.15 M sulphuric acid and the fresh regenerate for iron and uranium separation consists of 1.0-2.0 M sulphuric acid (hydrogen sulphate regeneration) and/or 0.01-0.15 M sulphuric acid with 40-80 g/l sodium chloride addition (chloride regeneration). If incomplete separation of the iron and uranium fractions occurs in the rich regenerate, the precipitation is carried out in two stages of firstly iron hydroxide separation by sodium hydroxide addition at pH 3.0-3.6 and then uranium oxide precipitation by hydrogen peroxide and sodium hydroxide addition at pH 3.2-4.0 without the need for intermediate chemical treatment of the clear phase.