Abstract: STUDY ON THE BEHAVIOUR OF TRITIUM IN PUREX PROCESSLuo Longjun;Hu Huaizhong;Sun Zhonghan;Chen Yongqing;Xu Fend;Li Xiacoing;Zhang Zepu;Gao Yuan;Liu Tianshu(China institute of Atomic Energy,P.O.Box275(26),Beijing 102413)Abstract:The behaviour of tritium in purex process is reported.The distribution coefficients of tritium and HNO_3 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 lst 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 10~4,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).Keywords:Tritium Tritiated water Tritium scrub mixer-settler Purex process Extraction