DISTRIBUTION OF NITROUS-ACID BETWEEN TRI-N-BUTYL PHOSPHATE N-DODECANEAND NITRIC-ACID/

The distribution of nitrous acid between tri-n-butyl phosphate (TBP) / n-dodecane (nDD) and nitric acid has been measured as functions of ni trous and nitric acid concentrations in the aqueous phase and function s of TBP and uranium concentrations in the organic phase. The extracti on of nitrous acid by TBP can be described by the following reaction: HNO2 + TBP0 reversible arrow HNO2 . TBP0, where the subscript ''o'' de note the organic phase. An empirical formula has been determined to ca lculate the thermodynamic equilibrium constant, K, of the reaction in the system TBP/nDD - nitric acid at any nitric acid concentration. The concentration constant, K', was found to be approximately 25 in the r ange from 0.01 M to 2.2 M of nitric acid in the aqueous phase.