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Pruett, D.J.
Oak Ridge National Lab., TN (USA)1986
Oak Ridge National Lab., TN (USA)1986
AbstractAbstract
[en] This report was prepared as a summary of a fourfold effort: (1) to examine schemes for defining and categorizing the field of separation science and technology; (2) to review several of the major categories of separation techniques in order to determine the most recent developments and future research needs; (3) to consider selected problems and programs that require advances in separation science and technology as a part of their solution; and (4) to propose suggestions for new directions in separation research at Oak Ridge National Laboratory (ORNL)
Primary Subject
Source
May 1986; 95 p; Available from NTIS, PC A05/MF A01 as DE86010429
Record Type
Report
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Country of publication
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INIS IssueINIS Issue
Pruett, D.J.
Oak Ridge National Lab., TN (USA)1986
Oak Ridge National Lab., TN (USA)1986
AbstractAbstract
[en] Solvent extraction and ion exchange have been the most widely used separation techniques in nuclear and radiochemistry since their development in the 1940s. Many successful separations processes based on these techniques have been used for decades in research laboratories, analytical laboratories, and industrial plants. Thus, it is easy to conclude that most of the fundamental and applied research that is needed in these areas has been done, and that further work in these ''mature'' fields is unlikely to be fruitful. A more careful review, however, reveals that significant problems remain to be solved, and that there is a demand for the development of new reagents, methods, and systems to solve the increasingly complex separations problems in the nuclear field. Specifically, new separation techniques based on developments in membrane technology and biotechnology that have occurred over the last 20 years should find extensive applications in radiochemical separations. Considerable research is needed in such areas as interfacial chemistry, the design and control of highly selective separation agents, critically evaluated data bases and mathematical models, and the fundamental chemistry of dilute solutions if these problems are to be solved and new techniques developed in a systematic way. Nonaqueous separation methods, such as pyrochemical and fluoride volatility processes, have traditionally played a more limited role in nuclear and radiochemistry, but recent developments in the chemistry and engineering of these processes promises to open up new areas of research and application in the future
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Secondary Subject
Source
1986; 28 p; 191. American Chemical Society national meeting; New York, NY (USA); 13-18 Apr 1986; Available from NTIS, PC A03/MF A01 as DE86009498
Record Type
Report
Literature Type
Conference
Report Number
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
Pruett, D.J.
Oak Ridge National Lab., TN (USA)1981
Oak Ridge National Lab., TN (USA)1981
AbstractAbstract
[en] The solvent extraction of heptavalent technetium from aqueous nitric or hydrochloric acid by tributyl phosphate in n-dodecane (TBP-NDD) has been studied over a wide range of TBP and acid concentrations at 25, 50, and 600C. The extraction was found to proceed according to the reaction 3 TBP + H+ + TcO4- → (HTCl4 . 3TBP). A discussion of possible reaction mechanisms is presented, along with values for ΔG, ΔH, ΔS and the equilibrium constant for the extraction reaction. Finally, evidence for the coextraction of technetium by uranyl ions is presented
Primary Subject
Source
1981; 34 p; Symposium on separation science and technology for energy applications; Gatlinburg, TN, USA; 5 - 8 May 1981; Available from NTIS., PC A03/MF A01
Record Type
Report
Literature Type
Conference; Numerical Data
Report Number
Country of publication
ACTINIDE COMPOUNDS, ACTINIDES, ALKANES, BUTYL PHOSPHATES, CHLORINE COMPOUNDS, DATA, ELEMENTS, ESTERS, HALOGEN COMPOUNDS, HYDROCARBONS, HYDROGEN COMPOUNDS, INFORMATION, INORGANIC ACIDS, KINETICS, METALS, NITRATES, NITROGEN COMPOUNDS, NUMERICAL DATA, ORGANIC COMPOUNDS, ORGANIC PHOSPHORUS COMPOUNDS, OXYGEN COMPOUNDS, PHOSPHORIC ACID ESTERS, REACTION KINETICS, SEPARATION PROCESSES, TRANSITION ELEMENTS, URANIUM COMPOUNDS, URANYL COMPOUNDS
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] The literature pertaining to the solvent extraction of heptavalent technetium and rhenium from aqueous solution by tributyl phosphate (TBP) has been compiled, critically evaluated, and supplemented with new data in some areas. The effects of adding mineral acids, alkali metal nitrates, alkali metal chlorides, uranyl nitrate, thorium nitrate, and plutonium(IV) nitrate to these systems were also examined. Discussions of the possible nature of the organic-phase complexes are presented, along with values of ΔG, ΔH, ΔS, and the equilibrium constant for the extraction reaction in several systems. Mathematical models correlating the distribution behavior over a wide range of conditions were also developed. Equations are given for calculating the distribution coefficients for the extraction of Re(VII) or Tc(VII) from 0.2 to 4 M HCl by 0.339 to 2.90 M TBP at 298 to 3330K. Equations are given for calculating the distribution coefficients under the same conditions, but with HNO3 (instead of HCl) present in the aqueous phase. 28 references, 27 figures, 3 tables
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Source
Dec 1984; 97 p; Available from NTIS, PC A05/MF A01 as DE85004948
Record Type
Report
Literature Type
Numerical Data
Report Number
Country of publication
BUTYL PHOSPHATES, CHLORINE COMPOUNDS, COMPLEXES, DATA, ELEMENTS, ENERGY, ESTERS, HALOGEN COMPOUNDS, HYDROGEN COMPOUNDS, INFORMATION, INORGANIC ACIDS, METALS, NITROGEN COMPOUNDS, NUMERICAL DATA, ORGANIC COMPOUNDS, ORGANIC PHOSPHORUS COMPOUNDS, OXYGEN COMPOUNDS, PHOSPHORIC ACID ESTERS, PHYSICAL PROPERTIES, SEPARATION PROCESSES, THERMODYNAMIC PROPERTIES, TRANSITION ELEMENT COMPLEXES, TRANSITION ELEMENTS
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
Pruett, D.J.; Sherrow, S.A.; Toth, L.M.
Research programs for Division of Chemical Sciences, Office of Basic Energy Sciences, Department of Energy1988
Research programs for Division of Chemical Sciences, Office of Basic Energy Sciences, Department of Energy1988
AbstractAbstract
[en] This task is concerned primarily with the fundamental chemistry of the actinide and fission product elements. Special efforts are made to develop research programs in collaboration with researchers at universities and in industry who have need of national laboratory facilities. Specific areas currently under investigation include: (1) spectroscopy and photochemistry of actinides in low-temperature matrices; (2) small-angle scattering studies of hydrous actinide and fission product polymers in aqueous and nonaqueous solvents; (3) kinetic and thermodynamic studies of complexation reactions in aqueous and nonaqueous solutions; and (4) the development of inorganic ion exchange materials for actinide and lanthanide separations. Recent results from work in these areas are summarized here
Source
Oak Ridge National Lab., TN (USA); 41 p; 1988; p. 1-10; Available from NTIS, PC A03/MF A01 as DE89003693
Record Type
Report
Report Number
Country of publication
Reference NumberReference Number
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AbstractAbstract
[en] Uranium and technetium in the product stream of the Purex process for recovery of uranium in spent nuclear fuel are separated by (1) contacting the aqueous Purex product stream with hydrazine to reduce Tc+7 therein to a reduced species, and (2) contacting said aqueous stream with an organic phase containing tributyl phosphate and an organic diluent to extract uranium from said aqueous stream into said organic phase
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17 Apr 1984; v p; US PATENT DOCUMENT 4,443,413/A/; U.S. Commissioner of Patents, Washington, D.C. 20231, USA, $.50; PAT-APPL-528279.
Record Type
Patent
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
Pruett, D.J.; Howerton, W.B.; Mailen, J.C.
Oak Ridge National Lab., TN (USA)1981
Oak Ridge National Lab., TN (USA)1981
AbstractAbstract
[en] Several methods for removing fluoride from aqueous nitric acid were investigated and compared with the frequently used aluminum nitrate-calcium nitrate (Ca2+-Al3+) chemical trap-distillation system. Zirconium oxynitrate solutions were found to be superior in preventing volatilization of fluoride during distillation of the nitric acid, producing decontamination factors (DFs) on the order of 2 x 103 (vs approx. 500 for the Ca2+-Al3+ system). Several other metal nitrate systems were tested, but they were less effective. Alumina and zirconia columns proved highly effective in removing HF from HF-HNO3 vapors distilled through the columns; fluoride DFs on the order of 106 and 104, respectively, were obtained. A silica gel column was very effective in adsorbing HF from HF-HNO3 solutions, producing a fluoride DF of approx. 104
Primary Subject
Source
Jun 1981; 26 p; Available from NTIS., PC A03/MF A01
Record Type
Report
Report Number
Country of publication
ALUMINIUM COMPOUNDS, CHALCOGENIDES, DISPERSIONS, FLUORINE COMPOUNDS, HALIDES, HALOGEN COMPOUNDS, HOMOGENEOUS MIXTURES, HYDROGEN COMPOUNDS, INORGANIC ACIDS, MIXTURES, NITRATES, NITROGEN COMPOUNDS, OXIDES, OXYGEN COMPOUNDS, SEPARATION PROCESSES, SOLUTIONS, TRANSITION ELEMENT COMPOUNDS, ZIRCONIUM COMPOUNDS
Reference NumberReference Number
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INIS IssueINIS Issue
AbstractAbstract
[en] The high selectivity of tributylphosphate (TBP) for U(VI) and Pu(IV) makes it possible to extract and purify these elements from the complex mixtures that result when irradiated nuclear fuel is dissolved in nitric acid. This selectivity, along with relatively high resistance of TBP to degradation by hydrolysis and radiolysis, combines to make the plutonium-uranium extraction (PUREX) solvent extraction process a remarkably successful method for the remote processing of large amounts of irradiated reactor fuel under harsh chemical conditions and in the presence of high radiation fields. However, while the selectivity of TBP for uranium and plutonium can be very high, it is not absolute; TBP extracts some fission products and transplutonium elements even under the most favorable conditions. Fortunately, the list of fission products that extract enough to be of concern in the PUREX process is relatively short. Ruthenium and zirconium (and zirconium's daughter, niobium) are by far the most troublesome. Technetium is not well-extracted by pure TBP, but coextracts with uranium, plutonium, and other metals to an appreciable extent. Iodine can react with the hydrocarbon diluents used in the process to form organic iodides that degrade process performance. Most of the discussion in this chapter focuses on these elements. The remaining fission products cause little trouble in the solvent extraction portion of the PUREX process, though some cause difficulties in off-gas treatment, waste management, or other parts of the fuel cycle; these latter elements will be only briefly discussed
Primary Subject
Secondary Subject
Source
Schulz, W.W.; Bender, K.P. (Westinghouse Hanford Co., Richland, WA (United States)) (eds.); Burger, L.L. (ed.) (Pacific Northwest Lab., Richland, WA (United States)); Navratil, J.D. (ed.) (New South Wales Univ. (Australia)); 260 p; ISBN 0-8493-6389-6;
; 1990; p. 81-121; CRC Press, Inc; Baca Raton, FL (United States); CRC Press, Inc., 2000 Corporate Blvd., N.W., Boca Raton, FL (United States) 33431

Record Type
Book
Country of publication
BETA DECAY RADIOISOTOPES, BETA-MINUS DECAY RADIOISOTOPES, CHEMICAL REACTIONS, ELEMENTS, EVEN-ODD NUCLEI, HALOGENS, HOURS LIVING RADIOISOTOPES, HYDROGEN ISOTOPES, INTERMEDIATE MASS NUCLEI, ISOMERIC TRANSITION ISOTOPES, ISOTOPES, KRYPTON ISOTOPES, LIGHT NUCLEI, MATERIALS, METALS, NONMETALS, NUCLEI, ODD-EVEN NUCLEI, PLATINUM METALS, RADIOACTIVE MATERIALS, RADIOISOTOPES, SEPARATION PROCESSES, TRANSITION ELEMENTS, YEARS LIVING RADIOISOTOPES
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AbstractAbstract
No abstract available
Primary Subject
Source
ANS winter meeting; San Francisco, CA (USA); 29 Nov - 4 Dec 1981; CONF-811103--; Published in summary form only.
Record Type
Journal Article
Literature Type
Conference
Journal
Transactions of the American Nuclear Society; ISSN 0003-018X;
; v. 39 p. 144-145

Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] The solvent extraction of heptavalent technetium from aqueous nitric or hydrochloric acid by tributyl phosphate in n-dodecane (TBP-NDD) has been studied over a wide range of TBP and acid concentrations at 25, 50, and 600C. The extraction was found to proceed according to the reaction 3TBP + H+ + TcO4- → (HTcO4 3TBP). A discussion of possible reaction mechanisms is presented, along with values for ΔG, ΔH, ΔS, and the equilibrium constant for the extraction reaction. Finally, evidence for the coextraction of technetium by uranyl ions is discussed. 10 figures, 5 tables
Primary Subject
Secondary Subject
Source
Symposium on separation science and technology for energy applications; Gatlinburg, TN, USA; 5 - 8 May 1981; CONF-810520--
Record Type
Journal Article
Literature Type
Conference; Numerical Data
Journal
Separation Science and Technology; ISSN 0149-6395;
; v. 16(9); p. 1157-1179

Country of publication
ADDUCTS, AQUEOUS SOLUTIONS, CHEMICAL REACTION KINETICS, DODECANE, ENTHALPY, ENTROPY, EQUILIBRIUM, EXPERIMENTAL DATA, HYDROCHLORIC ACID, MEDIUM TEMPERATURE, NITRIC ACID, ORGANIC SOLVENTS, QUANTITATIVE CHEMICAL ANALYSIS, QUANTITY RATIO, SOLVENT EXTRACTION, TBP, TECHNETIUM, TECHNETIUM COMPLEXES, TEMPERATURE DEPENDENCE, THERMODYNAMIC PROPERTIES
ALKANES, BUTYL PHOSPHATES, CHEMICAL ANALYSIS, CHLORINE COMPOUNDS, COMPLEXES, DATA, DISPERSIONS, ELEMENTS, ESTERS, HALOGEN COMPOUNDS, HOMOGENEOUS MIXTURES, HYDROCARBONS, HYDROGEN COMPOUNDS, INFORMATION, INORGANIC ACIDS, KINETICS, METALS, MIXTURES, NITROGEN COMPOUNDS, NONAQUEOUS SOLVENTS, NUMERICAL DATA, ORGANIC COMPOUNDS, ORGANIC PHOSPHORUS COMPOUNDS, OXYGEN COMPOUNDS, PHOSPHORIC ACID ESTERS, PHYSICAL PROPERTIES, REACTION KINETICS, SEPARATION PROCESSES, SOLUTIONS, SOLVENTS, TRANSITION ELEMENT COMPLEXES, TRANSITION ELEMENTS
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