Abstract
When the extraction is carried out in the system of thiocyanate-TBP- diluent, thorium, rare earth elements and scandium can be easily separated by selecting suitable diluents. For example, thorium (1g) can be separated from small amounts of rare earth elements (10μg) in the system of 15% TBP-carbon tetrachloride/2M ammonium thiocyanate. Scandium (100μg) can be separated from thorium (400mg) using the extraction system of 10% TBP-chloroform/1M ammonium thiocyanate.
The back extraction of the elements extracted into the organic phase is accomplished by 13N hydrochloric acid or nitric acid.
