Transuranium elements, extraction

Separation of Transuranium Elements by Phosphonate Extraction. Trans. 

Baybarz, R. D., Boyd Weaver and H. B. Kinser Separation of Transuranium Elements from Rare Earths by Tertiary Amine Extraction. Trans. Amer. Nucl. Soc. 5, 17 (1962). 

Zhu, Y., Song, C. 1992. Recovery of neptunium, plutonium and americium from highly active waste. Tri-alkyl phosphine oxide extraction. In Transuranium Elements A Half Century. Morss, L.R. Fuger, J., Eds. ACS, Washington, DC, pp. 318-330. 

Liu, X., Liang, J., Xu, J. 2004. Simplified Chinese TRPO process to extract and recover transuranium elements from high-level waste. Solvent Extr. Ion Exch. 22 (2) 163-173. 

Horwitz, E. P., D. G. Kalina, H. Diamond, et al. 1985. The TRUEX Process - A Process for the Extraction of the Transuranium Elements from Nitric Acid Wastes Utilizing Modified PUREX solvent. Solvent Extr. Ion Exch. 3, 75-109. 

It should be noted that some data on complexation of transuranium elements with various N-donor ligands, such as azide ion, isothiocyanate ion, amine-N-polycarboxylic and heterocyclic acids, 8-hydroxyquinoline and its derivatives, were published as early as 1950-1970 [42-77], The quantitative parameters of complexation (number and composition of complexes, stability constants, thermodynamic parameters) were determined using accessible at that time methods (spectrophotometry, potentiometry, ion exchange, solvent extraction). It was shown that transuranium elements in different oxidation states can form complexes with N-donor ligands. However, only presumptive conclusions regarding structure of complexes were drawn at that time,... 

Extraction Behaviour of the Transuranium Elements during Reprocessing... 

Most processes are developed for separation of an individual actinide or certain groups of actinides (e.g. U, Np and Pu by TBP extraction) from the waste. These processes are usually based on liquid/liquid extraction and ion exchange technique. More or less complicated processes lead to the separation of only one transuranium element. In these processes the radio-lytic destruction of the organic solvent or the ion exchanger causes some difficulties. 

The work on the synthesis of element 94 was headed by the famous American scientist G. Seaborg whose group discovered many transuranium elements. During the winter of 1940-1941 they studied the nuclear reaction U(d, 2n) which gave rise to the isotope neptunium-238. An alpha-active substance accumulated with time in the reaction product. The scientists extracted this substance and found... 

As for the natural radioactive elements the champions here are the Curies who extracted polonium and radium from uranium ore. G. Seaborg took part in the discoveries of eight transuranium elements (from plutonium to mendele-vium). G. Flerov and his large group from Dubna played a decisive role in reliable syntheses of elements 102-107. 

V. N. Kosyakov, E. S. Gureyev, and G. N. Yakolev, "Separation of Transuranium Elements by Solution Extraction in Alkyl Phosphoric Acids,"... 

The solvent extraction separation is one of the major research fields of the chemistry of transuranium elements. Nash and Choppin published selected papers on the separation science of f-elements in 1995 (Nash and Choppin 1995) and Yoshida et al. published Recent Progress in Actinide Separation Chemistry in 1997 (Yoshida et al. 1997).Mathuretal. (2001) reviewed actinide partitioning, and more recently, Tachimori and Morita (2009) issued a review article... 

The redox reaction has been utilized in the separation of light actinide elements (U, Np, and Pu) with both ion-exchange process and solvent extraction process. For trivalent heavy actinides with Z> 94 (except No), separation of these actinide ions from lanthanide ions is required for safe storage of long-lived nuclear waste and transmutation of these nuclides. Fundamental researches have widely been carried out by several groups for the purpose of quantitative separation of transuranium elements. Recent topics on the development and application of solvent extraction for the separation of transuranium elements are briefly summarized below. 

It has been more than fifty years since the discovery of the transuranium elements. The initial activities in this field established the fundamental solution and solid-state chemistry of the first two of these elements and their compounds under the auspices of the Manhattan Project. New separation methods including solvent extraction techniques and uranium isotope separation played a leading role in these programs. Tracer techniques were widely used to determine solubilities (or solubility liinits) of transuranium compounds as well as to obtain information about the coorination chemistry in aqueous solution. A little later, special solvent extraction and ion-exchange techniques were developed to isolate pure transplutonium elements on the milligram and smaller scale. The second edition of The Chemistry of the Actinide Elements, published in 1986 (i), covers most of these topics. A detailed overview of the history of transuranium chemistry is given in Transuranium Elements A Half Century (2). 

Seaborg, Glenn Theodore (1912-99) An American chemist noted as one of the discoverers of plutonium (plutonium-238 and plutonium-239). Gaining his doctorate in 1937 from the University of California, he was appointed professor of chemistry in 1945. He was responsible for nuclear chemical research at the Lawrence Radiation Laboratory and headed the Manhattan Project group from 1942 to 1946 that devised the chemical extraction processes used in the production of plutonium. He codiscovered nine other transuranium elements, including the element seaborgium, atomic number 106, which is named after him. He was awarded the Nobel Prize in Chemistry in 1951. 

Truex [Transuranium extraction] A process for removing transuranic elements during the processing of nuclear fuel by solvent extraction. Developed by E. P. Howitz at the Argonne National Laboratory, Chicago, IL. See also SREX. 

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