An improved PUREX process in technetium separation by stepwise reduction

An improved PUREX process in Tc separation is introduced in this paper. Experiments including we did and done by other investigators are cited in this paper to testify the feasibility of the process. The scheme of this process is as follows: First, to extract U, Pu and most Tc, Np into the organic phase, so the concentration of Tc in the high level liquid waste (HLLW) may be very low, which can alleviate the burden of Tc treatment in HLLW vitrification. Second, in the Pu and Np separation stage to reduce or complex Pu and Np using acetohydroxamic acid, this step separates Pu and Np from the organic phase. Next, to separate Tc from U, it can be realized easily by reducing Tc to lower valance using reductant such as hydrazine or quadrivalence U. By this technology, we may resolve the problems caused by Tc remained in the HLLW such as a long time surveillance of HLLW condensate or the risk of Tc transferring into the biosphere, and meanwhile the over-consumption of reductant in the U/Pu splitting stage can be avoided.