Study on the behaviour of tritium in Purex process

The behaviour of tritium in Purex process is reported. The distribution coefficients of tritium and HNO3 between 30% TBP-kerosene and aqueous phase are determined. The effects of γ-irradiation and uranium concentration on the distribution coefficient of tritium as well as the effect of γ-irradiation on the retention of tritium in organic solvent are studied. The scrub tests of extracting tritium from organic solvent show that scrubbing is a simple redistribution process of tritium between organic and aqueous phase. The behaviour of tritium in the 1st extraction cycle is tested on bench-scale, indicating that the decontamination factor of tritium in 1A mixer-settler (6 extraction stages and 9 scrub stages) is higher than 104, and most of the tritium is in the extraction section of 1A. The tritium remained in 1AP is easy to scrub into aqueous phase with a tritium scrub mixer-settler (five stages)