Bench scale studies have been made of the recovery of uranium from acid leach liquors (and slurries) by solvent extracting with di (2-ethylhexyl) phosphoric acid in an organic diluent. Uranium may be stripped from the organic solvent by either alkaline or acidic reagents, the former having been studied in greater detail. On the basis of these tests, a recovery process may be considered which shows promise both from the standpoint of operation and chemical costs. Under proper conditions, vanadium can also be extracted by the di (2-ethylhexyl) phosphoric acid and stripping again may be accomplished with either acidic or alkaline reagents. Preliminary studies have been made of these possibilities. In addition to di (2-ethylhexyl) phosphoric acid, some other organophosphorus acids, have been cursorily examined in respect to their extraction and/or stripping performance.

The conversion of UNH to UF4 and UF6, utilizing moving-bed techniques, is being studied; sufficient progress has been made that an evaluation of the process is warranted. The procedures under study, the Fluorox Process, have three major advantages: (1) substitution of HF for high-cost fluorine, (2) considerable reduction in HF requirements, and (3) marked reduction in plant-size and mechanical complexity.

Electrodialysis in an ion-exchange membrane cell was shown to be technically feasible for the concentration of an azeotropic mixture of HF and water. A flowsheet is presented for recovery of anhydrous HF by distillation and electrodialysis of the azeotropic residue. In the electrodialysis step, 2.6 kwhr of energy per pound of anhydrous product was consumed, with electricity at 1¢ per kilowatt-hour, the total operating cost of the electrodialysis equipment alone, including amortization, would be 6¢ per pound of HF.

Thorium, a fertile material, is of interest to the Reactor Program in the production of U233. Thorium can be extracted and processed to a very pure bulk metal for fabrication into solid fertile elements. There are advantages, technical and economic, for using fabricated bulk thorium dioxide rather than the metal in some applications. It is the purpose of this paper to point out these advantages and to present briefly the technology related to fabrication, radiation damage and chemical processing of ThO2.

Activity and ionic impurity specifications are presented for Thorex thorium nitrate products. Two sets of specifications are given, one set for direct handling during refabrication of production reactor thorium metal slugs and the second for refabrication of future power reactor thorium metal elements by semi-remote technics. Consideration was given to the health hazard problems associated with each process step between the Thorex process and final refabricated source material in order to arrive at these specifications.

A new gas-liquid countercurrent system (the ANCO system from Anisole-Complex) for the enrichment of boron isotopes has been developed. It is believed that use of this systems will result in a considerably lower unit cost for enriched boron-10 than was previously possible. The system utilizes the exchange reaction between BF3 (gas) and BF3·anisole (liquid) to concentrate boron-10 in the liquid phase. The single stage isotopic separation factor for this system has been found to vary from 1.039 at 0°C to 1.029 at 30°C. The isotopic exchange reaction has been shown to be rapid. Vapor pressures of the complex as a function of temperature have been measured and the heat of formation of the complex determined. Laboratory experiments show that quantitative removal of the BF3 from the complex can be accomplished by heating. A complete miniature ANCO plant was constructed and operated in the laboratory to test the feasibility of the system. The system was found to operate efficiently with a minimum of attention, and to enrich the isotopes of boron as expected. Based upon the experience obtained with the laboratory ANCO unit, a pilot plant large enough to utilize a 6-inch diameter exchange column was designed. The design calculations of …

New systems involving the exchange of boron between boron trifluoride and boron trifluoride addition compounds have been explored. These systems have large separation factors and potentially simple reflux mechanisms. A precise determination of this separation factor for the anisole-boron trifluoride system gave the value (see report). Boron exchange was found to occur between BF and BCl3. Several homogenous catalysts have been found which activate the hydrogen-water exchange, but none are adoptable to the production of deuterium because of the slow exchange rate. Platinum or platinum oxide may be usable as a heterogeneous catalyst with proper support or dispersion techniques. The high-pressure solubility of hydrogen in several amalgams was investigated in connection with a unique countercurrent exchange system. A proposed system involving isotopic exchange between lithium dipivaloylmethane in diethyl ether and lithium hydroxide in aqueous solution was shown to give little or no isotopic separation. Column studies of the carbonate system exchange reaction were concluded with a 40°C run. Slightly higher enrichment of N15 was obtained than at 30°C . The temperature dependence of all in this system was measured between 15 and 45°C. The factor increases with temperature, showing a tendency toward a maximum near 45°C. Isotopic exchange appears to …

The development of ionic methods for the determination of corrosion products in the highly radioactive Homogeneous Reactor (HR) fuels has been of major interest in the work of the Ionic Analyses Laboratory. Methods for the spectrophotometric determination of aluminum and for the polarographic determination of iron in HR fuels have been developed. The polarographic determination of molybdenum in uranyl sulfate solutions was studied. A polarographic method for the determination of zinc was developed. A fluorometric method for the determination of microgram amounts of fluoride was studied. Three organic reagents were investigated as precipitants for microgram quantities of zirconium in HR fuel. The automatic photometric titration technique was applied to the determination of thorium and of sulfate. A method was developed for the ionexchange separation and potentiometric titration of cobalt. The ultraviolet absorption spectra of technetium and rhenium were studied.

To better understand the solvent extraction process much effort has been and is being expended at ORNL and elsewhere to measure reaction kinetics of the extraction reactions. To date these efforts have been largely unsuccessful, due to the attempt to apply homogeneous reaction kinetics to two-phase systems. An optical method has been devised for analyzing the concentration profile in the vicinity of a quiescent interface during steady-state diffusion at rather large molecular fluxes. The system under study is the extraction of uranyl ion from water by a TBP solution. Considerable effort has been directed to eliminating leaks in the diffusion cell and testing the optical system/

Results of four experiemental runs in the Fluorox fluidized bed reactor system are reported. The engineering feasibility of UF6 production from UF4 by use of dry air of O2, 2UF4 + O2 = UF6 + UO2F2, in an Inconel fluidized bed reactor at 800-850°C was demonstrated in two experimental tests in which greater than 90% of the theoretical amount of UF6 was collected or measured. Two runs made with crude UF4 (produced from unpurified mill concentrate) as the feed material, showed that UF6 could be produced at 700-725°C but corrosion on Inconel was prohibitive.

Nuclear and radiation hazards have been investigated for all phases of operation to be carried out in the mechanical decladding of SRE fuel elements. The SRE fuel is 2.8% enriched with a maximum burnup of 1,000 Mvd/ton and minimum cooling of 120 days. Each element contains 9 kg of uranium metal (~2 kg U-235) and is made up from 84 slugs (3/4"D x 6'"), clad with (10 mil wall) stainless steel tubing. It is planned to ship the fuel from Santa Susana, California, to Oak Ridge in the modified PAR loop carriers, with a maximum of 10 elements being shipped in each carrier per trip.

The design of internally cooled electrical coils for the production of high frequency intensity magnetic fields presents many new aspects and combinations of the familiar modes of heat transfer. However, the customary methodology appears to be sufficient for preliminary analysis and understanding of those problems. This methodology comprises the derivation of a qualitative, approximate equation expressing the relative performance of the various parts of a system, followed by an examination of this equation in order to locate the limiting features of the system. These features are then investigated by more powerful methods, which in turn provide guidance for development research in the laboratory.

Volstility Pilot Plant Mark III Fluorinator will be a double-chamber type vessel, each chamber 2-1/2ft. by 16in. o.d. separated by a 5 in. pipe 15 in. long. ASME flanged and dished heads will be used for the chamber tops and conical sections with a 60º apex angle for the chamber bottoms. A new furnace designed to maintain the complete lower chamber (molten salt + freeboard) above melt temperature will eliminate past experiences of salt solidification on the wall, heads, and in or on the internal process lines. External pipe runs will be sutoresistance heated to allow melting and drain back of salt plugs. The upper chamber serves as a gas de-entrainment and solids precipitation device to retain most of the entrained salt and condensable fluorides in the 100-400°C temperature range.

A study was made of a method for the flame photometric determination of iron. In Part I of this report, the flame emission spectrum of iron, measured by means of a Beckman Model DU spectrophotometer with a flame attachment, is compated to that measured with an ORNL high-sensitivity, recording, single-beam instrument, in order to determine which instrument is best suited for this application. Although it was found that the Beckman product has the higher resolving power over the wavelength region of 360 to 400mu, it does no posses the sensitivity or ease of operation of the ORNL instrument. On this basis, the ORNL flame spectrophotometer is used in subsequent tests. After selecting the best-suited instrument for the flame photometric determination of iron, it was necessary to establish the optimum operating conditions for this particular method. These conditions are described in Part II.

The technique of high-frequency titrimetry has been applied to the determination of thorium, uranium, sulfate, and free acid. In Part I of this report, the reproducibility of the method for the titration of standard solutions which contained 50mg of thorium in the absence of interferences is established. The coefficient of variation of the method, under these conditions, was found to be less than one per cent. In Part II, the effect of uranium on the high-frequency titration of thorium, as well as the application of the method to actual samples, is discussed. Uranium in a ratio of 5 to 1 to thorium can be tolerated. When the method is applied to the analysis of representative samples, the coefficient of variation is one per cent.

A study of the thermodynamic properties of dilute aqueous hydrochloric acid solutions at elevated temperatures by an electromotive force method was undertaken for several reasons. First, a great need for fundamental information at elevated temperatures was evident from the growing number of industries making use of aqueous solutions at elevated temperatures. Second, the use of the hydrogen electrode against the silver-silver chloride electrode in dilute hydrochloric acid solutions promised to give fundamental thermodynamic information on an important electrode system as well as on hydrochloric acid over a wide temperature range.

The 0.045m UO2SO4, 0.036m CuSO4, 0.025 m H2SO4 solution (HRT fuel composition) was chemically stable during 1, 866hr of operation at 280ºC and 1500 psi. The system was pressurized by boiling a 0.4 gpm stream of the fuel in a titanium heat exchanger at 313ºC.

Considerable delay has occurred in getting ratification of the Eurochemic charter by 80% of the participating nations. The French, who were not expected to ratify the charter until an elected government was again established , actually ratified under de Gaulle late in 1958.

In order to make rational predictions of the operating characteristics of uranium anion exchange contactors, an understanding of the mechanism and kinetics of the exchange is necessary. Toward this objective an effort is being made to determine the equilibrium sorption isotherms and rates of sorption of uranium on the anion exchange resin Dovex 21K.

In order to make rational predictions of the operating characteristics of uranium anion exchange contactors, an understanding of the mechanism and kinetics of the exchange is necessary. Toward this objective an effort is being made to determine the equilibrium sorption isotherms and rates of sorption of uranium on the anion exchange resin Dovex 21K.

At the present time, plants in the 100-500Mv size range are more numerous and carry the greatest portion (over 50%) of the total steam-electric plant load in the U.S. utilities industry. The contribution of plants of over 1,000-Mv capacity is increasing more rapidly than any other size clarification and at present represents about 10% of the total capacity. By 1962 the TVA will have six plants with capacities of over 1,000-Mv. The largest steam-electric plant in the U.S. is the TVA plant at Kingston, Tenn., with a nameplate capacity of 1,440-Mv. Turbine-generator units are also following a trend of ever-increasing size. In present construction, the 150-200 Mv size range for units is the most common and represents the greatest contribution to capacity. Two units of 500-Mv nameplate rating each, the largest in the U.S., are on order by the TVA, and an 800 Mv unit is contemplated.

The fire involved approximately 30 liters of isopropyl alcohol as a result of the ignition of about 16-18 liters of isopropyl alcohol and a slurry of thoria and ammonium nitrate in a 20-liter glass carboy. This material was undergoing a volume reduction by boiling in a floor-type metal hood with Plexiglas sides and 3 sliding door on the front of ordinary glass. The alcohol vapor was vents directly into the hood (Fig1.)

The system Dovex 21K and aqueous uranyl sulfate solutions were studied in the solution compositions range: 0-0.005 mol/liter uranyl sulfate, 0.15 mil/liter total sulfate, 0.02 mol/liter H2SO4 (pH 2).It is shown that UO3SO4 and/or UO2(SO4)2-/2 are sorbed on the resin to form R2UO2(SO4)2. It is surmized that these same species are also involved at high uranyl concentrations and pH 2 it is suggested that U2O5SO4, U2O5(SO4)2-/2, and R2U2O3SO4 species may be involved.

After two batches (~ 340 kg) of fluoride salt from the ARE were reprocessed, pilot plant operations were terminated because of a leak through which an estimated 780 g of uranium (as UF6) escaped. Of the 21 kg of highly enriched uranium in the feed, 93.12% was collected as UF6 product, 0.13% represented measured losses, and 3.72% was unaccounted for (leak). An additional 3.03% was reclaimed from NaF beds and equipment washes. The product met both chemical purity and activity specifications for product level UF6. Decontamination from fission products was essentially complete. A gross gamma D.F. was apparently limited by the low activity of the feed salt.