HYDROXYLAMINE DERIVATIVE IN PUREX PROCESS. VI. STUDY ON THE PARTITION OF URANIUM/NEPTUNIUM AND URANIUM/PLUTONIUM WITH N,N-DIETHYLHYDROXYLAMINE IN THE PURIFICATION CYCLE OF URANIUM CONTACTOR

Abstract

Cascade extraction of uranium and cascade extraction-separation of uranium/neptunium and uranium/plutonium with 6 extraction stages and 6 stripping stages have been studied in the presence of N,N-diethylhydroxylamine (abbreviated as DEHAN) in nitric acid medium according to the experimental conditions of the purification cycle of uranium (referred to as contactor 2D) of the second cycle of the Purex Process. The percent recovery and material balance of U(VI) were found to be 99.997% and 101.5%, respectively. The decontamination factors and material balances of neptunium and plutonium from uranium were found to be 32.4, 25.3 and 102.5%, 105.7%, respectively. It suggests that the simultaneous separation of neptunium and plutonium from uranium is technically feasible for contactor 2D using N,N-diethylhydroxylamine as a salt-free reductant.

ACKNOWLEDGMENT

This work was financially supported by the Nuclear Industry Science Foundation of China.

The authors wish to thank Dr. Wu Guanmin for his assistance in the experiments and Dr. Yin Dongguang for helpful discussions. The authors also wish to thank Dr. G. Uchiyama, head of Process Safety Laboratory, Department of Fuel Cycle Safety Research, Japan Atomic Energy Research Institute, Dr. T. Tanaka, Mr. T. Maeda and M. Goto for their assistance in writing.