409 Matching Results

Search Results

Advanced search parameters have been applied.

AN OXYHYDROCHLORINATION PROCESS FOR PREPARING URANIUM-MOLYBDENUM REACTOR FUELS FOR SOLVENT EXTRACTION: LABORATORY DEVELOPMENT

Description: A flowsheet, based on laboratory-scale data, is presented for oxyhydrochlorination of 90% uranium --10% molyhdenum alloy with 15% HCl in air at 4OO deg C in 18 hr. Up to 90% of the molybdenum is volatilized during oxyhydrochlorination and another 3 to 6% is removed by a 2-hr treatment with pure hydrogen chloride at 400 deg C. Residual chloride is removed by a 4-hr treatment with moist air at 400 deg C, and the product uranium oxide is dissolved in 4M nitric acid to yield a stable solvent extraction feed solution of 1M uranium, 0.017M molybdenum, 175 ppm chloride, and 1.7M nitric acid. The stainless steel cladding of the original fuel would be removed mechanically and the core recanned in aluminum prior to transfer to the core processing facility. The aluminum can would be removed by hydrochlorination prior to core treatment. (auth)
Date: March 16, 1961
Creator: Gens, T.A.
Partner: UNT Libraries Government Documents Department

Separation of Metal Ions by Anion Exchange in Mixtures of Hydrochloric Acid and Hydrofluoric Acid

Description: Distribution coefficients were determined for the adsorption of more than 40 elements on anion-exchange resins from mixtures of HCl (0.1 to 12M) and HF (0.1-8M). Two resins, Dowex 1 x 10, 200 to 400 mesh and Dowex 1 x 4, 100 to 200 mesh, were used. Distribution coefficients were also determined for the adsorption of many elements on both resins from 0.1 to 12M HCl and 0.1 to 12M HF. Anion exchange in the presence of HF was found useful for separating impurities from various materials for their subsequent determination, and specific procedures used in our spectrochemical laboratory for this purpose are outlined. The results of a literature search on the use of anion exchange in hydrofluoric acid and fluoride-containing media are presented in an extensive bibliography.
Date: December 1978
Creator: Faris, J. P.
Partner: UNT Libraries Government Documents Department

THE ACTIVITY COEFFICIENTS OF HYDROCHLORIC ACID AND SODIUM CHLORIDE IN HYDROCHLORIC ACID-SODIUM CHLORIDE MIXTURES

Description: The activity coefficients of HCl and NaCl in HCl--NaCl mixtures were computed from literature data. The calculations are based on the observation that at constant ionic strength and temperature the logarithm of the activity coefficient of HCi in HCl--NaCl mixtures varies linearly with NaCl concentration. (auth)
Date: July 29, 1963
Creator: Lietzke, M.H. & Stoughton, R.W.
Partner: UNT Libraries Government Documents Department

Recovery of Uranium From Fiberglass Air Filters

Description: Abstract: Various procedures for extracting uranium from fiberglass air filters have been tested and compared. Satisfactory results which involve the least amount of handling are obtained by simply washing the material with hot 1:1 hydrochloric acid.
Date: August 5, 1946
Creator: Adams, R. H.; Rogers, J. A. & Brown, K. B.
Partner: UNT Libraries Government Documents Department

Separation of Aluminum Phosphate Minerals From Kaolinite by Selective Solution

Description: Abstract: Wavellite, crandallite, and millisite are completely dissolved by boiling samples for 20 minutes with 1+1 hydrochloric acid; only 1 percent of the aluminum present in kaolinite is dissolved. This method of decomposition can therefore be used for differentiating the aluminum present in wavellite, crandallite, and millisite form that in kaolinite in samples from the aluminum phosphate zone. This method should prove valuable in prospecting and benefication studies.
Date: September 1955
Creator: May, Irving & Smith, Roberta
Partner: UNT Libraries Government Documents Department

Extraction of short-lived zirconium and hafnium isotopes usingcrown ethers: A model system for the study of rutherfordium

Description: The extraction of zirconium and hafnium from hydrochloric acid media was studied using the crown ethers dibenzo-18-crown-6 (DB18C6), dicyclohexano-18-crown-6 (DC18C6) and dicyclohexano-24-crown-8 (DC24C8) as extractants. The goal was to find an extraction system that exhibits a high selectivity between the members of group 4 of the periodic table and is suitable for the study of rutherfordium. It was found that Zr and Hf are both extracted using DB18C6, DC18C6 and DC24C8. The extraction yield increases with increasing acid concentration and increasing concentration of crown ether. The extracted species most likely consists of an ion-association complex formed between a Zr or Hf chloro complex and a hydronium crown ether complex. Conditions can be found for each extractant that provide for the separation of Zr from Hf. This selective separation between Zr and Hf makes the extraction with crown ethers from HCl well suited to study the extraction behavior of Rf and compare it to the behavior of Zr and Hf. These extraction systems can be used to determine whether the extraction behavior of Rf is similar to Zr, similar to Hf or follows the trend established by the lighter homologs. The extraction kinetics are fast enough for the study of the 78-s isotope {sup 261}Rf.
Date: July 6, 2005
Creator: Sudowe, Ralf; Calvert, Michael G.; Dullmann, Christoph E.; Farina, Lindsy M.; Folden III, Charles M.; Gregorich, Kenneth E. et al.
Partner: UNT Libraries Government Documents Department

THERMODYNAMIC PROPERTIES OF DILUTE AQUEOUS HYDROCHLORIC ACID SOLUTIONS AT ELEVATED TEMPERATURES FROM ELECTROMOTIVE FORCE MEASUREMENTS (thesis)

Description: BS>Results of a study of thermodynamic properties of aqueous hydrochloric acid solutions are presented. A hydrogen electrode was used against a silver-silver chloride electrode at 25 to 275 deg C using hydrogen pressure of about 1 atm. and hydrochloric acid concentrations of 0.005 to 1.0 M. Electromotive measurement techniques are described and resulting data are tabulated. (J.R.D.)
Date: May 1, 1959
Creator: Greeley, R S
Partner: UNT Libraries Government Documents Department

Preparation of Americium Dioxide by Thermal Decomposition of Americium Oxalate in Air

Description: One hundred and seventy five grams of americium in a hydrochloric acid solution varying from 1 to 7 N was converted to americium dioxide. Americium oxalate was precipitated from 0.1 N HCI with 100% excess oxalic acid and was converted to the dioxide by calcination at 800 ts C in air. The solubility losses in the oxalate precipitation filtrate averaged approximately 7 mg/liter of solution, with a total loss of 0.09%. (auth)
Date: December 20, 1960
Creator: Baybarz, R. D.
Partner: UNT Libraries Government Documents Department

New Acid Stimulation Treatment to Sustain Production - Los Angeles Downtown Oil Field

Description: Hydrochloric acid stimulation was successfully used on several wells in the Los Angeles Downtown Field, in the past. The decline rates after stimulation were relatively high and generally within six months to a year, production rates have returned to their prestimulation rates. The wells in Los Angeles Downtown Field have strong scale producing tendencies and many wells are treated for scale control. Four wells were carefully selected that are representative of wells that had a tendency to form calcium carbonate scale and had shown substantial decline over the last few years.
Date: March 10, 2003
Creator: Russell, Richard C.
Partner: UNT Libraries Government Documents Department

Increased Oil Production and Reserves From Improved Completion Techniques in the Bluebell Field, Uinta Basin, Utah

Description: The Bluebell field is productive from the Tertiary lower Green River and Colton (Wasatch) Formations of the Uinta Basin, Utah. The productive interval consists of thousands of feet of interbedded fractured clastic and carbonate beds deposited in the ancestral Lake Uinta. Wells in the Bluebell field are typically completed by perforating 40 or more beds over 1000 to 3000 vertical ft (300-900 m), then stimulating the entire interval with hydrochloric acid. This technique is often referred to as the shot gun completion. Completion techniques used in the Bluebell field were discussed in detail in the Second Annual Report (Curtice, 1996). The shot-gun technique is believed to leave many potentially productive beds damaged and/or untreated, while allowing water-bearing and low-pressure (thief) zones to communicate with the wellbore. A two-year characterization study involved detailed examination of outcrop, core, well logs, surface and subsurface fractures, produced oil-field waters, engineering parameters of the two demonstration wells, and analysis of past completion techniques and effectiveness. The study was intended to improve the geologic characterization of the producing formations and thereby develop completion techniques specific to the producing beds or facies instead of a shot gun approach to stimulating all the beds. The characterization did not identify predictable-facies or predictable-fracture trends within the vertical stratigraphic column as originally hoped. Advanced logging techniques can identify productive beds in individual wells. A field-demonstration program was developed to use cased-hole advanced logging techniques in two wells and recompletion the wells at two different scales based on the logging. The first well was going to be completed at the interval scale using a multiple stage completion technique (about 500 ft [150 m] per stage). The second well will be recompleted at the bed-scale using bridge plug and packer to isolate three or more beds for stimulation. These recompletion will show ...
Date: April 1, 1998
Creator: Morgan, C.D. & Deo, M.D.
Partner: UNT Libraries Government Documents Department

Chemical vapor infiltration process modeling and optimization

Description: Chemical vapor infiltration is a unique method for preparing continuous fiber ceramic composites that spares the strong but relatively fragile fibers from damaging thermal, mechanical, and chemical degradation. The process is relatively complex and modeling requires detailed phenomenological knowledge of the chemical kinetics and mass and heat transport. An overview of some of the current understanding and modeling of CVI and examples of efforts to optimize the processes is given. Finally, recent efforts to scale-up the process to produce tubular forms are described.
Date: December 31, 1995
Creator: Besmann, T.M.; Stinton, D.P. & Matlin, W.M.
Partner: UNT Libraries Government Documents Department

Ion Association in High-Temperature Aqueous HCl Solutions. A Molecular Simulation Study

Description: The profiles of the potential of mean force for the <i>Cl<sup>-</sup> - H<sub>3</sub>O<sup>+</sup></i> pair, as predicted by two <i>ab initio</i> models, are determined by constraint molecular dynamics simulation at a near-critical condition. The corresponding association constants are then determined and compared with that from conductance measurements to test the reliability of the current simulation models for <i>HCl</i>.
Date: October 30, 1999
Creator: Chialvo, A.A.; Cummings, P.T.; Mesmer, R.E. & Simonson, J.M.
Partner: UNT Libraries Government Documents Department

The Dissolution of Iron and Nickel in Dilute Aqua Regia

Description: In laboratory studies the dissolution of iron in dilute nitric - hydrochloric acid mixtures shows an apparent reaction order of -0.62 with respect to HCl. No apparent order value for HNO/sub 3/ can be determined over the concentration ranges studied. Nickel dissolutions show apparent orders of 1.4 with respect to the HCl and 4.2 for HNO/sub 3/. Activation energies determined from 50 to 80 deg C are not constant, ranging from l0 to 20 kcal per mole for both metals. (arth)
Date: November 1, 1961
Creator: Cannon, R. D.
Partner: UNT Libraries Government Documents Department