Separation transplutonium

Ruehle jr., W. Separating Transplutonium Isotopes from Irradiated Plu-... 

Figure L Diagram of pressurized ion exchange system used to separate transplutonium elements...

Baybarz, R. D. (1965). Dissociation contents of the transplutonium chelates with diethylenetriaminepentaacetic acid (DTPA) and the application of DTPA chelates to solvent extraction separations of transplutonium elements from the lanthanide elements, J. Inorg. Nucl. Chem. 27,1831. 

Fig. 12.16 Flow sheets used for separation of transplutonium elements from irradiated Pu (a) France (Fontenay-aux-Roses) (b) United States (Oak Ridge National Laboratory). (Data from (a) Ref. 64 (b) Ref. 65.)...

Schulz, W. W. Navratil, J. D. Solvent extraction with neutral bidentate organic phosphorus reagents. In Recent Developments in Separation Science, Li, N. N. Ed. CRC Press Boca Raton, Florida, 1982 Vol. VII, pp. 31-72. Myaesoedov, B. F. Chmutova, M. K. New methods of transplutonium elements isolation, purification and separation. In Separation of f Elements, Nash, K. L. Choppin, G. R. Eds. Plenum Press New York, 1995 p. 11. 

Tachimori, S., Sato, A., Nakamura, H. 1979. Separation of transplutonium and rare-earth elements by extraction with di-A< -decyl phosphoric acid from DTPA solution. J. Nucl. Sci. Technol. 16 434 140. 

The ZEALEX Process Researchers from KRI have shown that the zirconium salt of dibutyl phosphoric acid (ZS-HDBP) was soluble in Isopar-L in the presence of 30% TBP. This super PUREX solvent, known as ZEALEX, extracts actinides (Np-Am) together with lanthanides and other fission products, such as Ba, Cs, Fe, Mo, and Sr from nitric acid solutions. The extraction yields depend on both the molar ratio between Zr and HDBP in the 30% TBP/Isopar-L mixture and the concentration of HN03 (232). Trivalent transplutonium and lanthanide elements can be stripped together from the loaded ZEALEX solvent by a complexing solution, mixing ammonium carbonate, (NH4)2C03, and ethylenediamine-N.N.N. N -tetraacetic acid (EDTA). An optimized version of the process should allow the separation of... 

Certain of the transplutonium elements are used extensively in nuclear gauges and in many other fields as well. Industrial-scale production of these man-made elements requires development and application of appropriate recovery, separation, and purification processes. 

This collection of the state-of-the-art papers emphasizes the continuing importance of industrial-scale production, separation, and recovery of transplutonium elements. Americium (At. No. 95) and curium (At. No. 96) were first isolated in weighable amounts during and immediately after World War II. Berkelium and californium were isolated in 1958 and einsteinium in 1961. These five man-made elements, in each case, subsequently became available in increasing quantities. 

Ross, R. G. "Industrial-Scale Production - Separation -Recovery of Transplutonium Elements," ACS Symposium, 2nd Chem. Congr. North American Continent, 1980. 

Treatment of irradiated targets. The chemical operations relative to the production of transplutonium elements (americium 243, curium 244) are all performed using a nitric acid medium. The highly corrosive nature of the solutions concentrated with Cl" ions, which were used in the USA for the development of the Tramex process (JO, and the instability of SCN" ions to radiation (12), led us to select nitric acid solution to perform the chemical separations. Once the medium was selected, it was necessary to find an adequate additive which, in combination with a suitable extractant, would allow solution of the main problem namely separation of the trivalent actinides from triva-lent lanthanides. 

Experience in the Separation and Purification of Transplutonium Elements in the Transuranium Processing Plant at Oak Ridge National Laboratory... 

The clarified Tramex product solution is divided into two or three batches (<35 g of curium or <19 g of 244 Qm pgr batch) and processed by LiCl-based anion exchange, which is discussed in detail in another paper at this symposium (10), to obtain further decontamination from rare earths and to separate curium from the heavier elements. In each run, the transplutonium and rare-earth elements are sorbed on Dowex 1-X10 ion exchange resin from a 12 hi LiCl solution. Rare earths are eluted with 10 hi LiCl, curium with 9 M LiCl, and the transcurium elements with 8 jl HC1. About 5% of the curium is purposely eluted along with the transcurium elements to prevent losses of 2498 which elutes immediately after the curium and is not distinguishable by the in-line instrumentation. The transcurium element fractions from each run are combined and processed in a second-cycle run, using new resin, to remove most of the excess curium. 

Collins, E. D. Benker, D. E. Chattin, F. R. Ore, P. B. Ross, R. G., "Multigram Group Separation of Actinide and Lanthonide Elements by Li Cl-Based Ion Exchange", paper presented at Symposium on Industrial-Scale Production-Separation-Recovery of Transplutonium Elements, 2nd Chem. Congr. North American Continent, Las Vegas, NV, 1980. 

Baybarz, R. D. Weaver, B. "Separation of Transplutoniums from Lanthanides by Tertiary Amine Extraction/1 ORNL-3185 (December 1961). 

Chromatographic Cation Exchange Separation of Decigram Quantities of Californium and Other Transplutonium Elements... 

This paper discusses the equipment and process steps used in the initial separation of transplutonium elements and presents some typical results. 

Campbell, D. O., "The Application of Pressurized Ion Exchange to Separations of Transplutonium Elements," Industrial-Scale Production-Recovery-Separation of Transplutonium Elements Symposium, ACS Second Chemical Congress, Las Vegas, Nevada, 1980. 

The Application of Pressurized Ion Exchange to Separations of Transplutonium Elements... 

The transplutonium elements and the rare earths, or lanthanides, are so similar chemically that what is true for one group is generally true for the other. In practice, process development work is usually carried out with lanthanides, and frequently, all the solutions end up as analytical samples. Transplutonium elements, in contrast, are so valuable that the goal is the maximum yield of pure products. Accordingly, the methods and equipment developed with rare earth separations are applied directly to heavy actinide production separations. These may be quite small in scale, but this is "production" for some of these elements. 

Figure 2. Elution curve given by flow-through a-detector during early pressurized ion exchange separation of transplutonium elements (34)...

Larger-scale separations of americium and curium are based on the pioneering work of Wheelwright and coworkers (24) and the very large-scale use of displacement development for commercial rare earth separations. Application of pressurized ion exchange to displacement development for transplutonium element separations has been pursued at SRL by Hale, Lowe, and coworkers (25, 26), and the work was reviewed in 1972 (27). 

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