SOLVENT EXTRACTION OF MINERAL ACIDS: PART III. SOLUTE–SOLVENT INTERACTION IN THE SYSTEM HYDROBROMIC ACID – WATER – TRI-n-BUTYL PHOSPHATE

Abstract

Evidence, based on physical–chemical measurements of the organic layers, has been presented to show that tributyl phosphate extracts hydrobromic acid as its disolvate in medium acid concentrations, and probably as monosolvate in high concentrations. The determination of water in the tributyl phosphate phases indicates that at low and medium acid concentrations the acid is extracted as its tetrahydrate, and at high concentrations as an unhydrated species. From these results, the formation of [(TBP)2.HBr.(H2O)6] and [TBP.HBr. (H2O)3] could be deduced.