Thermal Degradation of Organic Compounds in Radioactive Suspensions

Thermal degradation of radioactive concentrates in the oxidizing medium at temperatures of up to 900°C was studied by DSC–TG. The presence of significant amounts of organic compounds in the concentrates was confirmed. The degradation of organic compounds in the concentrates occurs in steps and is accompanied by thermal effects in the temperature range 170–900°С. Oxidative treatment of the concentrate with Fenton’s reagent decreases the content of organic compounds by a factor of 2–5. High-temperature drying of the concentrate at a temperature higher than 450°С allows virtually complete removal of organic compounds from the waste, which improves the safety of the long-term waste storage. The concentrate weight loss decreases as the drying temperature is increased. The high-temperature drying opens prospects for preparing compounds that will be safer from the viewpoint of final disposal.