An investigation on the dissolution of the uranium mineral brannerite

A number of different uranium minerals are processed in different regions of the world to produce the uranium that is used to generate electricity. The three main types of uranium minerals that are found at the world's single largest uranium bearing ore body (Olympic Dam, South Australia) are: tetravalent and hexavalent uraninite [UO2, UO3]; coffinite [U(SiO4)1-x(OH)4x]; and brannerite [U(Ti, Fe)2O6]. Detailed knowledge of the factors that influence the dissolution of uraninite are well known, yet little information on the dissolution of brannerite has been reported in the literature. In this study the influence of a number of parameters on the rate of UTi2O6 dissolution under acidic conditions were investigated. The parameters that were investigated included temperature, [H2SO4], total iron concentration and oxidation/reduction potential (ORP). Of these parameters acid concentration and temperature were found to have the most significant effect on the rate / overall extent of UTi2O6 dissolution under the test conditions used to gain an improved understanding on the leaching kinetics of synthetic brannerite.