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The transuranium elements: From neptunium and plutonium to element 112

Description: Beginning in the 1930`s, both chemists and physicists became interested in synthesizing new artificial elements. The first transuranium element, Np, was synthesized in 1940. Over the past six decades, 20 transuranium elements have been produced. A review of the synthesis is given. The procedure of naming the heavy elements is also discussed. It appears feasible to produce elements 113 and 114. With the Berkeley Gas-filled Separator, it should be possible to reach the superheavy elements in the region of the spherical Z=114 shell, but with fewer neutrons than the N=184 spherical shell. 57 refs, 6 figs.
Date: July 26, 1996
Creator: Hoffman, D.C.
Partner: UNT Libraries Government Documents Department

Transuranic Decontamination of Nitric Acid Solutions by the Truex Solvent Extraction Process: Preliminary Development Studies

Description: This report summarizes the work that has been performed to date at Argonne National Laboratory on the development of the TRUEX process, a solvent extraction process employing a bifunctional organophosphorous reagent in a PUREX process solverc (tributyl phosphate-normal paraffinic hydrocarbons). The purpose of this extraction process is to separate and concentrate transuranic (TRU) elements from nuclear waste.
Date: July 1984
Creator: Vandegrift, G. F.
Partner: UNT Libraries Government Documents Department

Special lecture in memory of Glenn Theodore Seaborg (19 April 1912 - 25 February 1999) Glenn T. Seaborg's multi-faceted career

Description: Glenn Theodore Seaborg (1912-1999) was a world-renowned nuclear chemist, a Nobel Laureate in chemistry in 1951, co-discoverer of plutonium and nine other transuranium elements, Chairman of the US Atomic Energy Commission from 1961-71, scientific advisor to ten US presidents, active in national and international professional societies, an advocate for nuclear power as well as for a comprehensive nuclear test ban treaty, a prolific writer, an avid hiker, environmentalist, and sports enthusiast. He was known and esteemed not only by chemists and other scientists throughout the world, but also by lay people, politicians, statesmen, and students of all ages. This memorial includes a brief glimpse of Glenn Seaborg's early life and education, describes some of his major contributions to nuclear science over his long and fruitful career, and highlights his profound influence on nuclear science, both in the US and in the international community.
Date: November 1, 2001
Creator: Hoffman, Darleane C.
Partner: UNT Libraries Government Documents Department

HISTORY OF THE ORIGIN OF THE CHEMICAL ELEMENTS AND THEIR DISCOVERIES.

Description: The origin of the chemical elements show a wide diversity with some of these elements having their origin in antiquity. Still other elements have been synthesized within the past fifty years via nuclear reactions on heavy elements, because these other elements are unstable and radioactive and do not exist in nature. The names of the elements come from many sources including mythological concepts or characters; places, areas or countries; properties of the element or its compounds, such as color, smell or its inability to combine; and the names of scientists. There are also some miscellaneous names as well as some obscure names for particular elements. The claim of discovery of an element has varied over the centuries. Many claims, e.g., the discovery of certain rare earth elements of the lanthanide series, involved the discovery of a mineral ore from which an element was later extracted. The honor of discovery has often been accorded not to the person who first isolated the element but to the person who discovered the original mineral itself, even when the ore was impure and contained many elements. The reason for this is that in the case of these rare earth elements, the ''earth'' now refers to oxides of a metal not to the metal itself. This fact was not realized at the time of their discovery, until the English chemist Humphry Davy showed that earths were compounds of oxygen and metals in 1808. In the early discoveries, the atomic weight of an element and spectral analysis of the element were not available. Later both of these elemental properties would be required before discovery of the element would be accepted. In general, the requirements for discovery claims have tightened through the years and claims that were previously accepted would no longer meet the minimum constraints now ...
Date: June 29, 2001
Creator: HOLDEN,N.E.
Partner: UNT Libraries Government Documents Department

Radionuclides in sediments and seawater at Rongelap Atoll

Description: The present concentrations and distributions of long-lived, man-made radionuclides in Rongelap Atoll lagoon surface sediments, based on samples collected and analyzed in this report. The radionuclides were associated with debris generated with the 1954 Bravo thermonuclear test at Bikini Atoll. Presently, only {sup 90}Sr and the transuranic radionuclides are found associated with the surface sediments in any quantity. Other radionuclides, including {sup 60}Co and {sup 137} Cs, are virtually absent and have either decayed or migrated from the deposits to the overlying seawater. Present inventories of {sup 241}Am and {sup 249+240}Pu in the surface layer at Rongelap are estimated to be 3% of the respective inventories in surface sediments from Bikini Atoll. There is a continuous slow release of the transuranics from the sediments back to the water column. The inventories will only slowly change with time unless the chemical-physical processes that now regulate this release to the water column are changed or altered.
Date: March 1, 1998
Creator: Noshkin, V.E.; Robison, W.L.; Eagle, R.J. & Brunk, J.L.
Partner: UNT Libraries Government Documents Department

Chemistry of the heaviest elements--one atom at a time

Description: In keeping with the goal of the Viewpoint series of the Journal of Chemical Education, this article gives a 75-year perspective of the chemistry of the heaviest elements, including a 50-year retrospective view of past developments, a summary of current research achievements and applications, and some predictions about exciting, new developments that might be envisioned within the next 25 years. A historical perspective of the importance of chemical separations in the discoveries of the transuranium elements from neptunium (Z=93) through mendelevium (Z=101) is given. The development of techniques for studying the chemical properties of mendelevium and still heavier elements on the basis of measuring the radioactive decay of a single atom (''atom-at-a-time'' chemistry) and combining the results of many separate experiments is reviewed. The influence of relativistic effects (expected to increase as Z{sup 2}) on chemical properties is discussed. The results from recent atom-at-a-time studies of the chemistry of the heaviest elements through seaborgium (Z=106) are summarized and show that their properties cannot be readily predicted based on simple extrapolation from the properties of their lighter homologues in the periodic table. The prospects for extending chemical studies to still heavier elements than seaborgium are considered and appear promising.
Date: January 1, 2000
Creator: Hoffman, Darleane C. & Lee, Diana M.
Partner: UNT Libraries Government Documents Department

TRUEX Hot Demonstration

Description: In FY 1987, a program was initiated to demonstrate technology for recovering transuranic (TRU) elements from defense wastes. This hot demonstration was to be carried out with solution from the dissolution of irradiated fuels. This recovery would be accomplished with both PUREX and TRUEX solvent extraction processes. Work planned for this program included preparation of a shielded-cell facility for the receipt and storage of spent fuel from commercial power reactors, dissolution of this fuel, operation of a PUREX process to produce specific feeds for the TRUEX process, operation of a TRUEX process to remove residual actinide elements from PUREX process raffinates, and processing and disposal of waste and product streams. This report documents the work completed in planning and starting up this program. It is meant to serve as a guide for anyone planning similar demonstrations of TRUEX or other solvent extraction processing in a shielded-cell facility.
Date: April 1990
Creator: Chamberlain, D. B.; Leonard, R. A.; Hoh, J. C.; Gay, E. C.; Kalina, D. G. & Vandegrift, G. F.
Partner: UNT Libraries Government Documents Department

STATUS OF RADIOACTIVE ELEMENTS IN THE ATOMIC WEIGHTS TABLE.

Description: During discussions within the Inorganic Chemistry Division Committee, that dealt with the Periodic Table of the Chemical Elements and the official IUPAC position on its presentation, the following question was raised. When the various chemical elements are presented, each with their appropriate atomic weight value, how should the radioactive elements be presented? The Atomic Weights Commission has treated this question in a number of different ways during the past century, almost in a random manner. This report reviews the position that the Commission has taken as a function of time, as a prelude to a discussion in Ottawa about how the Commission should resolve this question for the future.
Date: August 8, 2003
Creator: HOLDEN,N. E.
Partner: UNT Libraries Government Documents Department

Recent Work with the Transuranium Elements

Description: In this discussion of the heaviest known elements, the author describes some recent research which appears to offer the most promise for future investigations. As a general background, the author reviews briefly the history and properties of the transuranium elements.
Date: November 1, 1958
Creator: Seaborg, Glenn T.
Partner: UNT Libraries Government Documents Department

Magnesium transport extraction of transuranium elements from LWR fuel

Description: This report discusses a process of separating transuranium actinide values from uranium values present in spent nuclear oxide fuels which contain rare earth and noble metal fission products. The oxide fuel is reduced with Ca metal in the presence of CaCl{sub 2} and a U-Fe alloy containing not less than about 84% by weight uranium at a temperature in the range of from about 800{degrees}C to about 850{degrees}C to produce additional uranium metal which dissolves in the U-Fe alloy raising the uranium concentration and having transuranium actinide metals and rare earth fission product metals and the noble metal fission products dissolved therein. The CaCl{sub 2} having CaO and fission products of alkali metals and the alkali earth metals and iodine dissolved therein is separated and electrolytically treated with a carbon electrode to reduce the CaO to Ca metal while converting the carbon electrode to CO and CO{sub 2}. The Ca metal and CaCl{sub 2} is recycled to reduce additional oxide fuel. The U-Fe alloy having transuranium actinide metals and rare earth fission product metals and the noble metal fission products dissolved therein is contacted with Mg metal which takes up the actinide and rare earth fission product metals. The U-Fe alloy retains the noble metal fission products and is stored while the Mg is distilled and recycled leaving the transuranium actinide and rare earth fission products isolated.
Date: December 31, 1991
Creator: Ackerman, J.P.; Battles, J.E.; Johnson, T.R.; Miller, W.E. & Pierce, R.D.
Partner: UNT Libraries Government Documents Department

Uranium chloride extraction of transuranium elements from LWR fuel

Description: A process of separating transuranium actinide values from uranium values present in spent nuclear oxide fuels containing rare earth and noble metal fission products as well as other fission products is disclosed. The oxide fuel is reduced with Ca metal in the presence of Ca chloride and a U-Fe alloy which is liquid at about 800{degrees}C to dissolve uranium metal and the noble metal fission product metals and transuranium actinide metals and rare earth fission product metals leaving Ca chloride having CaO and fission products of alkali metals and the alkali earth metals and iodine dissolved therein. The Ca chloride and CaO and the fission products contained therein are separated from the U-Fe alloy and the metal values dissolved therein. The U-Fe alloy having dissolved therein reduced metals from the spent nuclear fuel is contacted with a mixture of one or more alkali metal or alkaline earth metal halides selected from the class consisting of alkali metal or alkaline earth metal and Fe or U halide or a combination thereof to transfer transuranium actinide metals and rare earth metals to the halide salt leaving the uranium and some noble metal fission products in the U-Fe alloy and thereafter separating the halide salt and the transuranium metals dissolved therein from the U-Fe alloy and the metals dissolved therein.
Date: December 31, 1991
Creator: Miller, W.E.; Ackerman, J.P.; Battles, J.E.; Johnson, T.R. & Pierce, R.D.
Partner: UNT Libraries Government Documents Department

Salt transport extraction of transuranium elements from LWR fuel

Description: This report discusses a process of separating transuranium actinide values from uranium values present in spent nuclear oxide fuels which contain rare earth and noble metal fission products. The oxide fuel is reduced with Ca metal in the presence of CaCl{sub 2} and a Cu-Mg alloy containing not less than about 25% by weight Mg at a temperature in the range of from about 750{degrees}C to about 850{degrees}C to precipitate uranium metal and some of the noble metal fission products leaving the Cu-Mg alloy having transuranium actinide metals and rare earth fission product metals and some of the noble metal fission products dissolved therein. The CaCl{sub 2} having Cao and fission products of alkali metals and the alkali earth metals and iodine dissolved therein is separated and electrolytically treated with a carbon electrode to reduce the CaO to Ca metal while converting the carbon electrode to CO and CO{sub 2}. The Ca metal and CaCl{sub 2} is recycled to reduce additional oxide fuel. The Cu-Mg alloy having transuranium metals and rare earth fission product metals and the noble metal fission products dissolved therein is contacted with a transport salt including Mg C1{sub 2} to transfer Mg values from the transport salt to the Cu-Mg alloy .hile transuranium actinide and rare earth fission product metals transfer from the Cu-Mg alloy to the transport salt. Then the transport salt is mixed with a Mg-Zn alloy to transfer Mg values from the alloy to the transport salt while the transuranium actinide and rare earth fission product values dissolved in the salt are reduced and transferred to the Mg-Zn alloy.
Date: December 31, 1991
Creator: Pierce, R.D.; Ackerman, J.P.; Battles, J.E.; Johnson, T.R. & Miller, W.E.
Partner: UNT Libraries Government Documents Department

Liquid membrane system for the removal and concentration of transuranic elements

Description: The goal of this program is to develop an efficient, reliable, and radiation-resistant modified liquid membrane system (MLMS) for the selective removal and concentration of transuranic elements (TRUs) and strontium-90 from dissolved Hanford sludge wastes. The efforts are divided into three categories: (1) demonstration and optimization of the MLMS for the TRUEX and SREX processes using simulant waste solution; (2) development of a radiation-resistant microporous divider and membrane module for testing with actual waste solutions; and (3) demonstration of the MLMS for the TRUEX and SREX processes using actual Hanford waste. Successful completion of these development efforts will yield a compact, versatile, and reliable MLMS for implementation with the TRUEX and SREX processes. The MLMS is simple, stable, more efficient, and easier to control and operate than conventional solvent-extraction processes, such as those employing centrifugal contactors. In addition, the MLMS process offers operational cost savings over the conventional technology, by exhibiting at least a 10% reduction in the consumption of extractant chemicals.
Date: December 31, 1996
Creator: Timmins, M.R.; Wysk, S.R.; Smolensky, L.A.; Jiang, D. & Lumetta, G.J.
Partner: UNT Libraries Government Documents Department

Preliminary engineering evaluation of heat and digest treatment for in-tank removal of radionuclides from complexed waste

Description: This report uses laboratory data from low temperature-ambient pressure digestion of actual complexed supernatant to evaluate digestion as a pretreatment method for waste in double-shell tanks 241-AN-102, 241-AN-107 and 241-AY-101. Digestion time requirements were developed at 100 degrees celsius to remove organic and meet NRC Class C criterion for TRU elements and NRC Class B criterion for 90Sr. The incidental waste ruling will establish the need for removal of 90Sr. Digestion pretreatment precipitates non radioactive metal ions and produces additional high-level waste solids and canisters of high level glass. This report estimates the amount of additional high-level waste produced and preliminary capital and operating costs for in-tank digestion of waste. An overview of alternative in-tank treatment methods is included
Date: September 29, 1995
Creator: Klem, M. J.
Partner: UNT Libraries Government Documents Department

Evaluation of the ACT*DE*CON{sup SM} process for treating gunite tank sludge

Description: A test was conducted to evaluate this process for selectively removing actinides from Gunite tank sludge. Mixed waste sludge from Gunite tank W-6 was subjected to the ACT*DE*CON selective leaching process. (Nearly all the TRU content was attributed to Pu.) The sludge sample was first washed with 0.01M NaOH to remove excess sodium and nitrate in the interstitial liquid supernatant. The washed wet solids were treated with the ACT*DE*CON solvent (aqueous carbonate solution containing a chelating agent and an oxidant), using a ratio of 20 ml solvent per gram wet solids. Sludge and solvent were separated by centrifugation, and the ACT*DE*CON treatment was repeated twice. Analyses showed that 71% of the solids in the sludge were dissolved while 80% of the TRU-waste components dissolved. Low separation of the TRU-waste components from other components of the sludge mixture is indicated. Almost all the U and Ca were removed from the sludge. For sludges where most of the TRU content is Pu, the ACT*DE*CON process as tested is not effective in rendering the sludge a non-TRU waste. It is recommended that ACT*DE*CON be optimized for this specific application and that other processes using different chelating and oxidizing agents be tested. Also, the ACT*DE*CON process should be tested on TRU mixed waste in which most of the TRU elements are not Pu.
Date: May 1, 1996
Creator: Spencer, B.B.; Chase, C.W. & Egan, B.Z.
Partner: UNT Libraries Government Documents Department

A technical review of the SWEPP gamma-ray spectrometer system

Description: The SWEPP Gamma-ray Spectrometer (SGRS) was developed by INEL researchers as a nonintrusive method of determining the isotopic ratios of TRU and U materials in a 208-liter waste drums. The SGRS has been in use at SWEPP since mid-1994. Enough questions have been raised regarding the system reliability and technical capabilities, that, coupled with a desire to procure an additional gamma-ray spectroscopy system in order to increase the drum throughput of SWEPP, have prompted an independent technical review of the SGRS. The author was chosen as the reviewer, and this report documents the results of the review. While the SGRS is accurate in its isotopic ratio results, the system is not calculationally robust. The primary reason for this lack of calculational reliability is the implementation of the attenuation corrections. Suggested changes may improve the system reliability dramatically. The SGRS is a multiple detector spectrometry system. Tests were conducted on various methods for combining the four detector results into a single drum representative value. No clear solution was reached for the cases in which the isotopic ratios are vertically segregated; however, some methods showed promise. These should be investigated further. 14 refs. , 15 figs., 23 tabs.
Date: March 1, 1996
Creator: Hartwell, J.K.
Partner: UNT Libraries Government Documents Department

Studies of the chemistry of transuranium elements and technetium at the Institute of Physical Chemistry, Russian Academy of Sciences, supported by the US Department of Energy

Description: Studies at Hanford in the 1980s revealed the potential for actinides to form stable soluble complexes in alkaline media, simulating radioactive tank waste. Pu(IV) hydrous oxide and Pu(VI) solubility increased with hydroxide concentration, ionic strength, and aluminate/carbonate concentrations. Subsequent contacts between US and Russian researchers in 1993 led to a technical literature review of the chemistry of TRU and Tc in alkaline media; this review addresses oxidation states, solubility, speciation, redox reactions, electrochemistry, radiation chemistry, and separations in alkaline media. As an outgrowth, a program of fundamental and applied chemistry studies of TRU and Tc is being conducted at IPC/RAS with US DOE support: solubility, redox reagents, coprecipitation, and radiation chemistry. This overview provides information on the Hanford Site tank waste system, US DOE technological needs, and IPC/RAS developments.
Date: April 1995
Creator: Peretrukhin, V. F. & Delegard, C. H.
Partner: UNT Libraries Government Documents Department

Impact of contributions of Glenn T. Seaborg on nuclear science

Description: Glenn Theodore Seaborg (1912-199) was a world-renowned nuclear chemist, a Nobel Laureate in chemistry in 1951, co-discoverer of plutonium and nine other transuranium elements, Chairman of the U.S. Atomic Energy Commission from 1961-71, scientific advisor to ten U.S. presidents, active in national and international professional societies, an advocate for nuclear power as well as for a comprehensive nuclear test ban treaty, a prolific writer, an avid hiker, environmentalist, and sports enthusiast. He was known and esteemed not only by chemists and other scientists throughout the world, but also by lay people, politicians, statesmen, and students of all ages. This memorial includes a brief glimpse of Glenn Seaborg's early life and education, describes some of his major contributions to nuclear science over his long and fruitful career, and highlights the profound impact of his contributions on nuclear science, both in the U.S. and in the international community.
Date: December 26, 2000
Creator: Hoffman, Darleane C.
Partner: UNT Libraries Government Documents Department

Plutonium Immobilization Can Loading FY98 Year End Design Report

Description: The Plutonium Immobilization Facility will immobilize plutonium in ceramic pucks and seal the pucks inside welded cans. Remote equipment will place these cans in magazines and the magazines in a Defense Waste Processing Facility (DWPF) canister. The DWPF will fill the canister with glass for permanent storage. This report summarizes FY98 Can Loading work completed for the Plutonium Immobilization Project and it includes summaries of reports on Can Size, Equipment Review, Preliminary Concepts, Conceptual Design, and Preliminary Specification. Plant trip reports for the Greenville Automation and Manufacturing Exposition, Rocky Flats BNFL Pu repackaging glovebox line, and vendor trips are also included.
Date: November 25, 1998
Creator: Kriikku, E.
Partner: UNT Libraries Government Documents Department

Plutonium Immobilization Can Loading Preliminary Specifications

Description: This report discusses the Plutonium Immobilization can loading preliminary equipment specifications and includes a process block diagram, process description, equipment list, preliminary equipment specifications, plan and elevation sketches, and some commercial catalogs. This report identifies loading pucks into cans and backfilling cans with helium as the top priority can loading development areas.
Date: November 25, 1998
Creator: Kriikku, E.
Partner: UNT Libraries Government Documents Department

Safety Analysis Report for Packaging (SARP) of the Oak Ridge National Laboratory TRU Californium Shipping Container

Description: An analytical evaluation of the Oak Ridge National Laboratory TRU Californium Shipping Container was made in order to demonstrate its compliance with the regulations governing off-site shipment of packages that contain radioactive material. The evaluation encompassed five primary categories: structural integrity, thermal resistance, radiation shielding, nuclear criticality safety, and quality assurance. The results of this evaluation demonstrate that the container complies with the applicable regulations.
Date: January 1, 1980
Creator: Box, W.D.; Shappert, L.B.; Seagren, R.D.; Klima, B.B.; Jurgensen, M.C.; Hammond, C.R. et al.
Partner: UNT Libraries Government Documents Department