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/

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.

Abstract: "An experimental study was made to determine the effective shielding provided by a modern reinforced-concrete office building (AEC Headquarters building) from nuclear fallout. Pocket ionization chambers were used for measurement of the radiation-field strength. Fallout was simulated with distributed and point-source configurations of Co-60 and Ir-192 sources. Four typical sections were selected for study, and experiments were performed on each. These included an external wing with exposed basement walls and an external wing with a buried basement. Roof studies were made on an internal wing with a full basement and on the east end of wing A, which has a thin-roof construction. The thick-roof construction of 8 in. of concrete and 2 in. of rigid insulation covers all the building except the east end of wing A, which has 4 in. of concrete and 2 in. of insulation."

In HAPO solvent extraction processes there are two independent aspects of nitrous acid chemistry. One concern the decomposition of the solvent through nitration reactions and the attendant problems. These reactions are autocatalytic in the presence of nitric acid and have threshold values for both temperature and nitric acid concentration for a given solvent below which nitrous acid disappears and above which it is generated with continuous destruction of the solvent. These reactions are identical to those found in the prior study of the hexone system.

This is the fifty-fourth progress report of the Laboratory for Nuclear Science at the Massachusetts Institute of Technology. Progress reported covers the period for Physics and Chemistry through April 30,1959. Progress is reported on: (1) Chemistry of the fission elements group, (2) Nuclear chemistry (inorganic) group, (3) Nuclear chemistry (organic) group, (4) Cosmic ray group, (5) High energy accelerator physics group, (6) Bubble chamber group, (7) Liner acceleratory group, (8) Rockefeller generator group, (9) ONR generator group, (8) Radioactivity group, (9) Cyclotron group, (10) Theoretical group, (11) Personnel listing.

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.

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.

A number of the questions which have been posed to us in the subject references are commented upon below. These have been reviewed by personanel of the Research and Engineering Operation and the Facilities Engineering Operation, Chemical Processing Department, and of the Chemical Research and Development Operation, Hanford Laboratories Operation. Particular acknowledment is given G. J Alkire, J. P. Duckworth, J. B. Fecht, R. G. Geier, E. R. Irish, H. M. Jones, G. C. Oberg, A. M. Platt, W. H. Reas, W. C. Schmidt, R. J. Sloat, W. H. Swift, M. T. Walling and L. L. Zahn of these organizations for assistance given assembling this information.

This report provides an overview of the creation of the Liquid Metal Fuel Reactor Experiment program. It furthers the work by constructing a single loop to test all the components required for the 16 loop reactor. This utility loop was also constructed to provide a facility for testing various components such as valves and flow meters.

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.

Abstract: "The niobium-carbon system has been determined by X-ray and metallographic examination of sintered and arc-cast alloys. Two carbides exist: hexagonal Nb2C with a limited range of homogeneity, and cubic NbC with a solubility range from 8.25 to 10.25 weight per cent carbon. Dilute alloys freeze by eutectic reaction at 2230 C. The solubility of carbon in niobium is 0.80 at the eutectic temperature, but this decreases rapidly with temperature. Metallographic evidence indicates a peritectic reaction between melt, Nb2C, and NbC; alloys richer in carbon than NbC freeze by eutectic reaction."

The HAPO Critical Incident Alarm, Model I, is an instrument designed to give an audible and visual alarm signal in the event of a critical incident to which it is exposed. There will be thirty-one (31) of these instruments installed and several spares located in the various manufacturing buildings in the Chemical Processing Department where there exists any possibility of a critical incident occurring. The instrument is intended as a post or after-the-fact warning device. It will offer no protection prior or leading up to, nor prevent, a critical incident. They are intended to be operated from the 115 V. A.C., 60 C.P.S. emergency line power. The instrument is self-contained, including the radiation detector, and will be calibrated to alarm at 500 mr/hour in a gamma field.

Nearly all nuclear reactors being designed and built today- whether for research, power, or productions of fissionable materials- use recirculating fluids for cooling. However, a number of production reactors are still operating with single-pass cooling by treated natural water. The Hanford Atomic Products Operation of the General Electric Company presently operates production reactors for the AEC at Richland, Washington. The first reactors were built during World War II, and utilized a standard water treatment which was designed to provide large quantities of settled, filtered Columbia River water for once-through cooling.

Because of the excessive vertical fragility and high replacement costs of mice-window G-M tubes used in vertical and horizontal lead-pig shelf counters, it was requested that a simple system of conversions to reliable scintillation detection be accomplished.

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.

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.

During the period when the writer mixing fuel element was being evaluated, a small Litton glass lathe and a General Electric Fillerarc welder were used to weld the mixing spool to the fuel element. Due to the condition of these units and to the numerous difficulties encountered with them, it was deemed necessary to design and procure a semi automatic welding unit which could weld in excess of three hundred fuel elements per day.

Technical report of an investigation to determine a suitable material for sintering and casting of braze rings. Braze rings afford an excellent means of preplacing braze alloy on tube to head joints of radiators, heat exchangers, and similar applications. A cast ring is especially desirable because of its increased strength. Previous efforts at casting had used welding grade carbon blocks with the desired ring cavities machined into their surface. Conclusion: Stackpole grade 331 electro-graphite provided the best results of the materials investigation. It is hard and more readily machinable with conventional tools than other grades. Carbon, in general, proved to be more satisfactory especially due its ease and speed of fabrication.

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.

The thickness of an oxide film on phosphor bronze helices was determined by first establishing the oxygen content of the helix "as received" and after cleansing with nitric acid. Based on the assumption that the difference between these two values was the oxygen in the film, and that the film consisted entirely of cupric oxide, the thickness of the film was calculated from the density of cupric oxide, weight of the film, and surface area of film. A value of 1080 A was calculated as the thickness by this method.

The final percentage of xenon created by fission in uranium and plutonium is a function of the neutron flux intensity. The flux dependence results because axenon 133 and 135 can be converted to a a stable xenon isotope by neutron capture instead of decaying into cesium.

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.

Technical report describing the process to determine the fusion welding characteristics of Haynes Alloy #25 as applied to TLJ-100530, Corrosion Loops. Hayes Stellite Alloy #25 is a cobalt-base alloy for corrosion resistant high temperature applications. This material, when welded by the inert gas shielded tungsten arc method, produces sound ductile joints. Material thicknesses greater than 12 gauge require standard joint preparations, a V joint being preferred up to 1/4 inch and a U joint for greater thicknesses. Welding heat should be kept to a minimum followed by fast cooling. The molten metal is very fluid and may present difficulties when position welding.