Mass spectrometric study of the deterioration of polystyrene-based ion-exchangers.
A mass spectrometric study of the aging effects in polystyrene-based ion-exchangers has been made. Fragments in the m/e range 10-70 were examined and attributed to OH(+), H(2)O(+), CO(+), CO(+)(2), supplemented by SO(+) and SO(+)(2) from sulphonic-acid cation-exchangers. Ion-current intensities were found to be dependent on the state of the resin.
Radioisotope studies of carboxyl sites on strong acid and strong base ion-exchange resins derived from polystyrene.
The pH-dependent distribution of carrier-free radioisotopes between aqueous phases at constant ionic strength and polystyrene-divinylbenzene type exchangers reveals the presence of a secondary exchange function attributable to carboxyl groups. Cation- and anion-exchangers of the sulphonate and quaternary ammonium types possess this additional cation-exchange capacity which is, however, relatively very low in currently available commercial resins. Its influence on separations involving radioisotopes of high specific activity is discussed.
Systematic Separation of Fission Products by Solvent Extraction Method
A new scheme for separating fission products, zirconium-niobium-95, cerium-144, promethium-147, yttrium-90, strontium-90, ruthenium-106 and cesium-137, by the four-step liquid-liquid extractions was presented. First, zirconium-95 and niobium-95 were extracted from a 5 M hydrochloric acid solution into chloroform with cupferron. Second, rare-earth nuclides, cerium-144, promethium-147 and yttrium-90 were extracted from an acetate buffered solution of pH 4 to 5 into chloroform with cupferron. Third, strontium-90 was extracted from an acetate buffered solution of pH 8 into hexone (methyl isobutyl ketone) with TTA (2-thenoyltrifluoroacetone). Fourth, ruthenium-106 was extracted from 5 m hydrochloric acid solution with TBP (tri-n-butyl phosphate)-kerosene in the presence of stannous chloride or extracted with TBP in the presence of hydroxylamine. then cesium-137 was left in the last aqueous solution. Strippings of nuclides extracted in the organic phases could be attained by shaking each organic phase with nitr...