Radiation-Chemical Resistance of Anion Exchangers and Safety of Sorption Processes in Nitric Acid Media: V. Thermochemical Degradation Dynamics of VP-1AP Anion Exchanger

摘要

Thermal degradation of VP-1AP anion exchanger and its mixtures with HNO_(3) was studied in open vessels at 40 to 260℃. The anion exchanger ignites only after drying and heating to 220-260℃. Heating VP-1AP mixtures with 3-12 M HNO_(3) to 100℃ is accompanied by gas evolution at a rate of 0.6 l min~(-1) (l_(sorb))~(-1). Removal of the aqueous phase from the mixtures at 130-170℃ initiates intensive oxidation. It is accompanied by a temperature jump in the sorbent phase and by gas evolution acceleration and can be regarded as thermal explosion. Mixture preheating and irradiation reduce the thermal explosion "onset" temperatures.