Separation of plutonium from

Uranium-239 [13982-01 -9] has a half-life of 23.5 min neptunium-239 [13968-59-7] has a half-life of 2.355 d. Recycling or reprocessing of spent fuel involves separation of plutonium from uranium and from bulk fission product isotopes (see Nuclearreactors, chemical reprocessing). 

Stanley G. Thompson joined my group on October 1, 1942 and it fell to his lot to discover the process that was chosen for use at Clinton Laboratories (in Tennessee) and the Hanford Engineer Works (in the state of Washington) for the separation of plutonium from uranium and the immense intensity of radioactive fission products with which it was produced in the nuclear chain reactors. Again I turn to my journal to tell the story ... 

Livingstone et al. [87] carried out double tracer studies to optimise conditions for the radiochemical separation of plutonium from large volumes of seawater. 

Optimize Conditions for the Radiochemical Separation of Plutonium from Large Volume Seawater Samples, in Reference Methods for Marine Radioactivity Studies II. Ruthenium, Silver, Iodine, Zirconium, and the Transuranic Elements, IAEA Tech, Rep, Ser, (1975) 169, 69. 

Gal, I., and A. Ruvarac The separation of plutonium from uranium and fission products on zirconium phosphate columns. J. Chromatogr. [Amsterdam] 13, 549 (1964). 

Brambilla, G. Caporali, G. "Process for the Pyrochemical Separation of Plutonium from Irradiated Nuclear Fuels", Ger. Offen. 2 611 333, 1976. 

Separation of Plutonium from Air-monitoring Samples. Plutonium-238 2 6 yPu and 21+0Pu have been introduced into environment because of the experiments of nuclear explosion in air and of some accidents of the artificial satellites. Analysis of the plutonium is needed to elucidate the distribution of the plutonium in air and the rate of descent to the surface. For this purpose analytical procedures have been developed and utilized for routine measurements of the air-borne plutonium (18). 

Before solvent extraction, the feed was treated with manganous nitrate and less than equivalent permanganate to convert plutonium to Pu(VI). Tests in miniature mixer-settlers with synthetic feed solution but not containing Cf showed acceptably small concentrations of actinides in the aqueous waste (1AW) and organic raffinate (1CW) streams, and also acceptable separation of plutonium from curium and americium. 

Tributyl phosphate (TBP) is the most versatile agent for the extraction of uranium and plutonium from fission products and also for separation of plutonium from uranium. A 30% solution of TBP in normal hydrocarbons is the usual organic phase in the Purex process. The U and Pu are extracted by TBP as unionized complexes, free of hydration water, and solvated by a definite number of TBP molecules. The complexforming reactions proceed according to the following ... 

Separation of plutonium from the uranium in the TBP phase proceeds by countercurrent stripping of the plutonium into dilute nitric acid, which reduces the Pu to the Pu soluble species. The uranium remains in the organic phase. This countercurrent stripping section is followed by a scrubbing section that completes the removal of the plutonium from the uranium held in the TBP phase. 

Although TBP is a relatively stable organic compound, it does undergo slow hydrolysis to form di-n-butyl phosphate (DBP). Although the presence of DBP increases the distribution coefficients of uranium, plutonium, and other actinides, it interferes with the separation of plutonium from uranium, and it makes complete stripping of these elements difficult. DBP forms an insoluble compound with thorium. DBP formation is appreciable only when the... 

The next step in the Purex process after primary decontamination is separation of plutonium from uranium. This is done by reducing plutonium to the trivalent state, in which it is inextractable by TBP, while leaving the uranium in the extractable hexavalent condition. Reductants that have been used for this purpose include Fe, U, hydroxylamine, or cathodic reduction. 

USE As absorbent for rutin and quercetin in bydrolysis of ribonucleic acid in separation of plutonium from irradiated uranium. 

USE In the separation of plutonium from fission products mamif of optical flint glass,... 

The following examples are for the separation of plutonium from uranium similar procedures involving the same basic principles have been devised to separate Np and Am. The initial starting material in plutonium extraction is a solution of the uranium fuel element (plus its aluminum or other protec-... 

Rathore et al. [65] studied the separation of plutonium from low plutonium content acidic waste using HFSLM technique impregnated with TBP. They fabricated the hollow-fiber test module using 20 Im of 33.91 cm surface area and 9 cm length. The waste solution was containing... 

Procedure 6, Separation of Plutonium from Uranium and Fission Products in Irradiated Reactor Targets R. G. Hart, M. Lounsbury, C, B. Bigham, L. P. V. Corriveau, F. Girardi (Ref. 167)... 

Procedure 9a. Separation of Plutonium from Irradiated Uranium R. O. Lingjaerde (Ref. 255)... 

Procedure 9b, Separation of Plutonium from Uranium Metal. J. Rydberg (Ref. 341) Outline of Method... 

Pietri CE, Freeman BP, Weiss JR (1981) Qirantitative ion exchange separation of plutonium from impurities, NBL-298... 

Separation of uranium from plutonium Separation of plutonium from uranium Decontamination of fission products from plutonium Decontamination of fission products from uranium Plutonium recovery, %... 

In recent years interest has focused on liquid/liquid systems, particularly on emulsions and phase transfer agents. Although large numbers of examples of reactions can be found in the literature, there are few reactor designs that can be used in an industrial context. One such electrolytic cell is a pulse column reactor (Fig. 5.12), which was originally designed for the separation of plutonium from uranium. 

The most widely employed method for plutonium reprocessing used today in almost all of the world s reprocessing plants is the Purex (plutonium-uranium reduction extraction) process. Tributylphosphate (TBP) is used as the extraction agent for the separation of plutonium from uranium and fission products. In effecting a separation, advantage is taken of differences in the extractability of the various oxidation states and in the thermodynamics and kinetics of oxidation reduction of uranium, plutonium, and impurities. Various methods are in use for the conversion of plutonium nitrate solution, the final product from fuel reprocessing plants, to the metal. The reduction of plutonium halides with calcium proved to be the best method... 

In contrast to the very high levels of uranium enrichment required by weapons programs, power reactors use either natural (unenriched) uranium as the basis of their fuel, or relatively low levels of enrichment, up to about 4%. Similarly with plutonium, the isolation of pure Pu required for successful weapons design is not a priority for plutonium use in breeder reactors or for its recycling as Mixed OXide fuel (MOX) for use in current thermal reactors. The resultant fuels are not bomb material and cannot be used directiy for weapons production. However, the processes that are essential for the enrichment of uranium or for the separation of plutonium from irradiated fuel are essentially the same in both civil and military applications. 

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