Leaching of brannerite in the ferric sulphate system. Part 2: Mineralogical transformations during leaching
Embargoed until 15 November 2017.
Available under License Creative Commons Attribution Non-commercial No Derivatives.
*Subscription may be required
Brannerite, UTi2O6, is the most common refractory uranium mineral and is the most important uranium ore mineral after uraninite and coffinite. In order to develop an effective treatment method for the hydrometallurgical extraction of uranium from ores containing brannerite, it is necessary to understand the chemistry of the leaching process. Part 1 of this series described the results of a study of the chemical reaction mechanisms of brannerite under conditions similar to those used industrially. In this paper, the mineralogical data obtained from samples collected during the leaching work is used to derive further insight into the transformations that take place during leaching. Detailed characterisation of the brannerite feed specimen and leach residues was carried out using surface imaging and X-ray diffraction techniques. It was shown that the brannerite specimen is heterogeneous, consisting of at least two phases. The brannerite phase was metamict and showed signs of natural alteration to fine-grained (10-20 nm) crystalline anatase. Comparisons between the feed and residues showed that the X-ray amorphous materials, in particular lead and silicon enriched areas identified near the anatase were most susceptible to leaching while the crystalline material was relatively resistant to leaching. These results demonstrate that the extent of brannerite alteration and its texture are important considerations to the hydrometallurgical behaviour of a particular ore along with the typical concerns such as grade, liberation size and gangue mineralogy.
|Publication Type:||Journal Article|
|Murdoch Affiliation:||School of Engineering and Information Technology|
|Copyright:||© 2015 Published by Elsevier B.V.|
|Item Control Page|