New separation process for neptunium, plutonium, and uranium using butyraldehydes as reductants in reprocessing

Journal Article · Tue Jun 01 00:00:00 EDT 1993 · Nuclear Technology; (United States)

OSTI ID:6557214

Uchiyama, Gunzo; Fujine, Sachio; Hotoku, Shinobu; Maeda, Mitsuru ^[1]

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1. Japan Atomic Energy Research Inst., Ibaraki (Japan)

A new neptunium, plutonium, and uranium separation process using n- and iso-butyraldehydes as reductants for Np(VI) and Pu(IV), respectively, is described for nuclear fuel reprocessing. A kinetics study and a chemical flow sheet study are conducted to develop the selective separation process for neptunium, plutonium, and uranium. In the kinetics study, it is found that n-butyraldehyde reduces Np(VI) to Np(V) in the Purex solution but does not reduce Pu(IV) and U(VI), and iso-butyraldehyde reduces Np(VI) and Pu(IV) but does not reduce U(VI). Based on these results, a new process to separate neptunium, plutonium, and uranium selectively is proposed. The process consists mainly of three steps: the codecontamination step, the neptunium separation step [in which Np(VI) extracted by a solvent of 30% tri-n-butyl phosphate (TBP)/n-dodecane together with Pu(IV) and U(VI) is reduced to Np(V) by n-butyraldehyde and is back-extracted from the solvent], and the uranium/plutonium (U/Pu) partition step using iso-butyraldehyde as a Pu(IV) reductant. In the chemical flow sheet study, the effectiveness of the separation process is demonstrated by the use of miniature mixer-settlers. In the neptunium separation step, [approximately]99.98% of the neptunium extracted by the 30% TBP/n-dodecane solvent along with U(VI) in the uranium/neptunium coextraction step is reduced by n-butyraldehyde and separated from the uranium stream. In the U/Pu partition step, >99% of the plutonium is reduced by iso-butyraldehyde and separated from the uranium stream.

• OSTI ID: 6557214
• Journal Information: Nuclear Technology; (United States), Journal Name: Nuclear Technology; (United States) Vol. 102:3; ISSN 0029-5450; ISSN NUTYBB
• Country of Publication: United States
• Language: English

Related Subjects

050800* -- Nuclear Fuels-- Spent Fuels Reprocessing
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400105 -- Separation Procedures
ACTINIDES
BUTYL PHOSPHATES
ELEMENTS
ENERGY SOURCES
ESTERS
EXTRACTION
FUELS
MATERIALS
METALS
NEPTUNIUM
NUCLEAR FUELS
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
PERFORMANCE
PHOSPHORIC ACID ESTERS
PLUTONIUM
REACTOR MATERIALS
REDUCING AGENTS
REPROCESSING
SEPARATION PROCESSES
SOLVENT EXTRACTION
SPENT FUELS
TBP
TRANSURANIUM ELEMENTS
URANIUM