SOLID-PHASE STRIPPING OF RADIONUCLIDES FROM COMPLEXONE SOLUTIONS IN DENSE CARBON DIOXIDE

摘要

The present investigation is aimed at developing a method for CO_2 recycle at decontamination of different materials without pressure change in system. The work is concerned with uranium and plutonium sorption on solid acids and their salts from dense CO_2 media. It is shown that 80 - 83% U may be stripped from its complexes dissolved in 452 by dihydrate of oxalic acid and 97 - 100% are stripped by ammonium carbonate. The use of aminoacetic acid enables to strip ～30% U and 40% Pu from supercritical 452 solutions and ～32% U and 60% Pu from liquid 452. It is found that the amount of sorpted uranium decreases with increase of HNO_3 concentration in 452 stream.