Thermal Stability of Irradiated VP-1AP Anion Exchange Resin

The effect of irradiation of a strongly basic vinylpyridine anion exchange resin of the VP-1AP grade in nitrate form on the onset temperatures of exothermic reactions, thermal effects and the composition of gaseous thermolysis products of VP-1AP was studied. It was established that the onset temperatures of exothermic reactions for an irradiated anion exchange resin are reduced by 59–100°C. The total thermal effect of thermolysis of the irradiated sorbent is 67% less than that of the non-irradiated one. An analysis of the composition of the gaseous thermolysis products of the VP-1AP irradiated anion exchange resin showed that at the first stage of thermolysis, the functional groups of the sorbent are predominantly decomposed. At higher temperatures, the process of degradation of the styrene-divinylbenzene anion exchange resin matrix was ​detected. The significant influence of irradiation on the conditions for the safe use of anion exchange resins during separation of radionuclides from nitric acid solutions was demonstrated.