Simplified Chinese TRPO process to extract and recover transuranium elements from high-level liquid waste

The Chinese trialkyl phosphine oxides (TRPO) process is effective for recovery of transuranium elements from high-level liquid waste (HLLW). Integration of the TRPO process with the current Purex process will simplify both processes. With this viewpoint, a simplified TRPO process is proposed in this paper. The original process with two strip sections for U and Np + Pu has been changed to one (NH4)(2)CO3 strip section. The simplified process was tested with simulated HLLW. The strip ratios of U(VI), Np(IV) and Pu(IV) are above 99.8% in 3-stage countercurrent strip experiment with 80 g/L (NH4)(2)CO3. The cross-contamination of U, Np, Pu, and Nd in other process streams is quite low. In the whole of the process experiments, no precipitation or third phase occurs in any process stream. After convenient conversion treatment with 15 mol/L HNO3 the recovered U, Np, and Pu can be extracted with 30% TBP/kerosene, indicating the feasibility to return them to the Purex process for further purification.