Solvent extraction studies on thorium sulphate and halides

The effect of water-miscible alcohols, acetone and haloacids in the aqueous phase of sulphuric acid solutions has been studied on the extraction of thorium sulphate and halides by bis(2-ethylhexyl) phosphoric acid (HDEHP) and tri-n-butyl phosphate (TBP). The partition coefficient (E) is greatly affected by these additives, and this gives useful separations from many other elements. Besides, the log-log relationship between the E values and solvent concentration leads to some suggestions on the extraction mechanisms of this mixed system.