PROPERTIES AND CLEANUP OF DEGRADED TRIBUTYL PHOSPHATE—AMSCO SOLUTIONS AND THE RELATIVE STABILITIES OF ALTERNATIVE EXTRACTANT-DILUENT SYSTEMS

摘要

The formation and chemical properties of the major degradation products of several diluents in contact with acid nitrate solutions have been studied, together with (l) methods for purifying degraded diluents,n(2)methods of pretreating the diluent to minimize degradation, andn(3) the relative stability of several extractant-diluent systems. Emphasis was on Amsco 125-82, a specially treated naphtha used extensively at ORNL as a diluent for tributyl phosphate, a prominent extractant in liquid-liquid extraction systems used to recover uranium from aqueous solutions containing many elements.nAccelerated degradation of the diluent, usually containing 1 M tributyl phosphate (TBP), was induced by boiling with nitric acid or by irradiating (Co60 gamma rays) while agitating the solvent phase with nitric acid. Nitroparaffins, RN02, were the major degradation products and were formed at twice the rate when TBP was present during degradation. Under the conditions of degradation, a 100-whr/liter exposure was practically equivalent to 11 hr of boiling with 2 M HN03, as shown by Zr-Nb95 extraction, total organic nitrogen analysis, and spectrophotometric analysis.