Hot test of trialkyl phosphine oxide (trpo) for removing actinides from highly saline high-level liquid waste (hlow)

摘要

The TRPO extraction process for partitioning of actinides from high saline HLLW was studied. A hot test was carried out in a counter current mode with genuine HLLW by using a miniature centrifugal contactor set. The 30percent(v/v) TRPO-kerosene was used as extractant. The genuine highly saline HLLW was obtained from a reprocessing plant. The solution was diluted to 2.7 times and the concentrtion of HNO_3 was adjusted to 1.08mol/L at the same time. The results of the hot test were very attractive. Actinides as well as ~(99)Tc were effectively separated from the HLLW by TRPO extraction. The decontamination factors (D.F) for total alpha and ~(99)Tc activities are 588 and 125 respectively. Am, Np-Pu, and U were well stripped by 5.5mol/L HNO_3, 0.6mol/L H_2C_2O_4 and 5percentNa_2CO_3, respectively. Their separation was very efficient, and cross contamination was very low. The HLLW become a non-alpha waste after partitioning. The volume reduction factor is 39.4 for alpha waste.