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The crystal structure of thorium nitrate

Description: From introduction: "Studies were made of single crystals of thorium nitrate hydrate which we had available in this laboratory and from these we were able to determine the unit cell and find the thorium positions. These crystals contain on the order of six water molecules per thorium atom, but the exact composition is in some doubt."
Date: November 20, 1950
Creator: Templeton, David H. & Dauben, Carol H.
Partner: UNT Libraries Government Documents Department

The Heat of Formation of Thorium Sesquisulfide

Description: Abstract: "The heat of solution of thorium sesquisulfide was determined in 6.000 molar HCl at 25 C to ascertain the stability of the thorium (III) halides. The molal heat of formation of Th2S3 from rhombic sulfur and crystalline thorium is calculated as 258.6 kcal."
Date: April 7, 1953
Creator: Eyring, LeRoy & Westrum, Edgar F., (Jr.)
Partner: UNT Libraries Government Documents Department

Final Report on Purification of Thorium Nitrate by Solvent Extraction With Tributyl Phosphate: 1. Laboratory Investigations

Description: Report discussing laboratory investigations of thorium nitrate purification. Batch equilibrium data, solubility data, viscosity data, density data, and the results seven batch countercurrent extraction tests and two selective stripping tests are included.
Date: July 31, 1952
Creator: Ewing, R. A.; Fishel, J. B.; Kiehl, S. J., Jr.; Sharpe, R. E. & Bearse, A. E.
Partner: UNT Libraries Government Documents Department

Final Report on Purification of Thorium Nitrate by Solvent Extraction With Tributyl Phosphate: 2. Mixer-Settler Pilot Plant Investigations

Description: From abstract: "This report describes the construction and operation of a mixer-settler pilot plant for the purification of mantle-grade thorium nitrate. The liquid-liquid extraction process utilized 30% tributyl phosphate - 70% 'Solvesso-100' as the organic solvent and nitric acid as the salting agent. Continuous steady-state operation of the equipment was demonstrated, with very good recovery of thorium."
Date: July 31, 1952
Creator: Burkhart, C. A.; Foley, D. D.; Retzke, F. A.; Filbert, Robert B. & Clegg, John W.
Partner: UNT Libraries Government Documents Department

A Glossary of Uranium- and Thorium-Bearing Minerals

Description: Glossary of minerals containing uranium and thorium. "In the index there are 325 entries which represent 81 species containing uranium and thorium as major constituents, 39 species containing small amounts of uranium and thorium, 29 species which should be tested for uranium and thorium, and 13 species which have been reported to contain impurities or intergrowths of uranium, thorium, or rare-earth minerals."
Date: January 1950
Creator: Frondel, Judith Weiss & Fleischer, Michael
Partner: UNT Libraries Government Documents Department


Description: Thorium oxide is formed by the calcination of thorium oxalate precipitated under carefully controlled conditions. Material is produced with mean particle diameters of 1 to 5 mu . Some of the thorium oxide had uranium added to it by decomposing uranyl carbonate on the thorium oxide followed by calcination. Most of the oxides prepared were calcined to 1000 deg C or more and size classified to remove particles greater than 10 mu . The oxides were prepared in 150-lb batches, with a complete cycle requiring 24 hr. (auth)
Date: December 22, 1959
Creator: Johnsson, K.O. & Winget, R.H.
Partner: UNT Libraries Government Documents Department

Extraction chromatography: Progress and opportunities

Description: Extraction chromatography provides a simple and effective method for the analytical and preparative-scale separation of a variety of metal ions. Recent advances in extractant design, particularly the development of extractants capable of metal ion recognition or of strong complex formation in highly acidic media, have significantly improved the utility of the technique. Advances in support design, most notably the introduction of functionalized supports to enhance metal ion retention, promise to yield further improvements. Column instability remains a significant obstacle, however, to the process-scale application of extraction chromatography. 79 refs.
Date: October 1, 1997
Creator: Dietz, M.L.; Horwitz, E.P. & Bond, A.H.
Partner: UNT Libraries Government Documents Department

Preparation and Properties of Refractory Sulfides

Description: From abstract: "The methods of preparation of the sulfides of cerium, thorium, uranium, and barium are discussed. Where necessary, the apparatus are described. Procedures for the handling and grinding of the sulfides and hydrides which are used for their preparation are given...The physical, mechanical, chemical, and thermodynamic properties are given for various sulfide refractories which have been developed at the Berkeley, California chemical laboratories."
Date: 1948
Creator: Brewer, Leo; Bromley, Leroy; Gilles, Paul. & Lofgren, Norman
Partner: UNT Libraries Government Documents Department


Description: An investigation was made of the feasibility of producing pure Th compounds from monazite sand by a process involving the digestion of the sand with H/sub 2/SO/sub 4/ and separation of Th from the rare earths by solvent extraction. Direct extraction was not practicable. Precipitation of the sulfate from the system with lime and HNO/sub 3/ was tried and found to be partially successful but impracticable because of the large losses of Th by occlusion in the precipitate. A successful method for producing tributylphosphate-extractable solution was found, consisting of neutralizing the original solution to precipitate the heavy metals as phosphates, and, after filtering and washing, dissolving this precipitate in HNO/sub 3/. (auth)
Date: June 30, 1950
Creator: Whatley, M.E. & Bridger, G.L.
Partner: UNT Libraries Government Documents Department


Description: The solvent extraction of thorium with 42.5% TBP in a Decalin diluent was studied in a compound pulse column. The HETS for the extraction section of the column was 4.7 feet. A discussion of the method of gaphical calculations of a compound column is included. (auth)
Date: July 14, 1958
Creator: Dunn, W.E.
Partner: UNT Libraries Government Documents Department

Molecular models for actinide speciation

Description: Much effort has been devoted to the development of sensitive spectroscopic techniques for the study of actinide speciation based on the sensitivity of f-f electronic absorption bands to oxidation state and ligation of the actinide ions. These efforts assume that data obtained in such studies will be interpretable in terms of changes in complexation of the metal center. However, the current understanding of 5f electronic structure is based on data from solid state doped single crystals. In those studies, the local coordination geometry about the central actinide ion is maintained in an almost perfect high-symmetry environment and will have little relevance for species in solution where deviations from perfect high symmetry tend to be the rule rather than the exception. The authors have developed a vigorous research program in the systematic preparation and spectroscopic characterization of synthetic actinide complexes (Th, U, Np, and Pu) in which they can control nuclearity, oxidation state, and molecular structure. These complexes have been used to determine how observable electronic transitions are perturbed in response to structural changes in the complex in solution. From the spectra obtained for these model complexes, the authors have found that the f-f transitions naturally fall into obvious groupings by coordination number and symmetry by which they can now differentiate between monomeric, dimeric, and trimeric species in solution. The study of radionuclide speciation is fundamentally important to the determination of radionuclide solubility in the groundwater at Yucca Mountain.
Date: June 1, 1994
Creator: Clark, D.L.; Watkin, J.G.; Morris, D.E. & Berg, J.M.
Partner: UNT Libraries Government Documents Department


Description: Molten salts provide the basis of a new family of liquid fuel power reactors. The range of solubility of uranium and thorium compounds makes the system flexible, and allows the consideration of a variety of reactors. Suitable salt mixtures have meltirg points in the 85O to 95O deg F range and will probably prove to be sufficiently compatible with known alloys and to provide lorg-lived components, if the temperature is kept below 13OO deg F. Thus the salt systems naturally tend to operate in a temperature region suitable for modern steam plants and achieve these temperatures in unpressurized systems. Some economic and other considerations are made. (T.R.H.)
Date: October 10, 1957
Creator: McPherson, H.G.
Partner: UNT Libraries Government Documents Department