Gasses evolved by 60Co radiation degradation of strongly acidic ion exchange resins

Abstract

AbstractThe irradiation damage and stability of polystyrene—divinylbenzene and phenol—formaldehyde sulfonic acid ion exchange resins was investigated by determination of the radiolytic gases. A 440 curies 60Co radiation source was used. Commercial resins, Dowex 50W ×10 and Zeo‐Karb 215, were prepared under strict conditions in free acid and in salt forms, in an excess of deaerated water, swollen with a known amount of water, and in a very dry state. A series of 6 equal samples were exposed to absorbed doses of 50–200 Mrad at a dose rate 2.5 × 105 rad/hr. The gas analysis shows a very good linear does dependence of the evolved hydrogen and carbon monoxide. The linearity of carbon dioxide is good for Dowex 50W X10 but less pronounced for Zeo‐Karb 215. Sulfur dioxide is at least partially produced by direct action and is consumed by secondary reactions during irradiation.Under chosen experimental conditions the evolved hydrogen amounts for the absorbed dose 1 Mrad from 0.3 to 670 μmoles H2/eq. resin. The values for carbon dioxide and carbon monoxide are: 1.4–170 μmoles COs/eq. and 0.4–5.3 μmoles CO/eq. The corresponding G values are: 0.001–1.7 for hydrogen, 0.007–0.43 for carbon dioxide, and 0.002–0.027 for carbon monoxide. The G values for sulfur dioxide, calculated from the lowest absorbed doses, are between 0.001 and 0.87.