SOME EFFECTS OF RADIATION ON SOLVENT EXTRACTION PROCESSES

Abstract

The yield of total acid, G/sub acid/, in the radiolysis of tributyl phosphate-Amsco 125-82 solutions is 2.7 times the electron fraction of TBP, or approximately 2.7 times the weight fraction of TBP, per 100 ev of energy absorbed by the solution. Dibutyl phosphoric acid, DBPA, constitutes about 85% of the acid. Radiolysis of TBP also results in the conversion of abcut 0.9 molecules of TBP to a polymer per 100 ev of energy absorbed. Uranium extraction-stripping tests with an 8 stage spinner column have shown that one mole of uranium is retained in the organic phase during the stripping operation per mole of DBPA added pnior to the extraction operation. On the basis of a tentative molecular weight of 848 g/mole, the polymer retains in the organic phase during stripping operations about 1.2 moles of uranium per mole of polymer added prior to extraction. In addition to polymer and acids, condensed phase radiolysis prcducts include olefins, whose yield, expressed as G/sub c=c/, or number of double bonds formed per 100 ev of energy absorbed, decreases from ca 4 to 1 as the TBP concentration increases from 4.5 to 100 wt.%. Diethyl carbcnate (DEC) was tested for uranium retention and fission product decontamination properties. After irradiation to the 400 watt-hr/liter level, the uranium retention by DEC on stripping is decreased, rather than increased. Although -decontamination was adversely affected, ore resistant t -decontamination was essentially unaffected by irradiation to this level. (auth)