Abstract. The separation of uranyl nitrate from aqueous solutions of 0.635 M thorium nitrate, 3 M nitric acid and 3 M calcium nitrate by extraction with organic solvents has been investigated. Solvents which gave good separations were 2-tthyl hexyl acetate, ethyl benzoate, n-butyl either and beta-beta- dichloroethyl ether. In general, higher esters, ethers and alcohols are better for separating uranium from thorium that the lower homologues. Several solvents were tested at lower nitric acid concentrations. Dibutyl cellosolve gave a very good separation when the solution was 0.1 M nitric acid. Of the solvent mixtures studied that of equal parts of n-butyl ether and dibutyl cellosolve gave a good separation.

Introduction. It has been known for a long time that thorium is precipitated by oxalic acid in acid solutions, but a survey of the literature showed no study of the limits of the acidity and oxalic acid excess which yield quantitative results. V. I. Spitzin reports on the solubility of thorium oxalate in varying concentrations of several acids, but the effect of an excess oxalic acid is not included. Since solutions are sometimes presented for analysis that contain more than the recommended two per cent mineral acid, it would be advantageous to be able to quantitatively remove the thorium without otherwise altering the solutions. This was especially of interest in solutions containing bismuth, since it was hoped that some amounts of thorium could be precipitated in nitric acid solutions containing large quantities of bismuth. In removing the bismuth, first by a bismuth oxychloride precipitation, thee is every opportunity for carrying of the thorium.

Technical report with six sections describing the process: (1) The reaction of HN)3 with HSCN; (2) The distribution of nitric acid between hexone and water; (3) The distribution of HSCN between hexone and water; (4) The solubility of thorium sulfate in various extraction solutions; (5) The distribution of protoactinium and fission elements between hexone and aqueous thiocyanate solutions; and (6) Separation of uranium from thorium by extraction into hexone as UO2(SCH)a.

Technical report describing two experiments performed to compare the amounts of fission gases swept out of UNH solution with those amounts swept out of PU solution under idential condiditons. The charge wire technique was used. The essential date and the results are given in tables in the report.

Abstract. The physico-chemical methods of determining nitric acid and thorium nitrate in solutions containing these two materials were investigated. Conductimetric titration with sodium hydroxide can be used to determine nitric acid accurately. the titration of thorium nitrate requires a separate standardization of the base however, since a basic salt is precipitated rather the normal hydroxide. The titration of thorium is reproductible however, so and empirical standardization can be used. The measurement of the specific gravity and refractivity of the solutions provides a method of determining the concentrations in terms of these two variable. Equations for the concentrations in terms of specific gravity and refractively are given, both in pure solutions and in those saturated with methyl isobutyl ketone.

Technical report describing the purification and separation by distillation of UO2F2 from D2O. In the experiment which is discussed 2,129.6 lbs of UO2F2 were dissolved in 6,605 lbs of D2O. The average isotopic purity of the D2O decreased during the distillation from 99.77% to 99.73%. The dissolved impurities were less than those present originally in the heavy water.

Technical report. Numerous application of various column adsorption techniques to inorganic analytical chemistry have appear in the literature. The comparatively recent introduction of ion exchange resins has resulted in the development of efficient, simple, and rapid column adsorption methods. the principal service of column adsorption methods to analytical chemistry is that of providing a relatively simple means of separating an element in a sufficiently pure state so that a direct precipitation, ignition, and weighting, for example, will suffice to complete the quantitative analysis. Systems involving uranyl nitrate will naturally be emphasized in this report but information will be included concerning the separation of the individual members of a series from one another, such as in the alkaline earths and the rare earths.

Technical report: Measurements have been made on the equilibrium between Cu, Cu2+, U4+, and UO22+ in H2SO4 in an attempt to establish the value of the U4+ - UO22+ couple potential. The value of the formal potential for the U3+ - U4+ couple in 1N HCl at 0 degrees C was determined to be + 0.65 v.

Abstract. A satisfactory method has been found for dissolving thorium metal and thorium oxide in heat-treated 25-12 stainless steel vessels without excessive corrosion of the vessels. The dissolution medium consists of strong HNO3 containing a small amount of fluoride or fluo-silicate. the fluoride required has no harmful effects on a subsequent solvent-extraction step for a separation of uranium isotopes from the dissolved thorium.

Technical report that attempts to bring together the various chemical procedures which proved most useful in studying the results of cyclotron bombardment or small scale neutron bombardments of heavy element targets. The report is limited to the elements of the "actinide", or second rare earth series, starting with thorium and including the newly discovered elements of atomic number 95 and 96. Every attempt is made to include all details necessary so this report can serve as a practical laboratory guide. The report covers separation problems, time factors, and dealing with dangerously radioactive targets.

Abstract. Thorium peroxide was precipitated from thorium nitrate solutions containing varying amounts of sulfate ion and of hydrogen ion. The washed solids were analyzed both wet and dry. Analyses were made for thorium, peroxide oxygen, sulfate, nitrate, and water contents. X-ray powder photographs of the dried samples by W.H. Zachariasen showed the presence of only two phases. When precipitated from high sulfuric acid, the solid phase was isomorphous with Th(OO)SO4.3H20. More weakly acid solutions whose sulfate content was varied over wide limits [SO4--/Th(IV) (in solution before precipitation) = 0.005 to 67.0] yielded a solid, isomorphous with thorium peroxide nitrate and containing 3.0 to 3.8 peroxide oxygen atoms for each thorium atom. The sulfate content of this latter phase varied continuously between the limits SO4--/Th(IV) = 0.34 to 0.01 with nitrate ion present when the sulfate content was very low. This continuous variation in composition is in agreement with the previously proposed structure of this phase.

Technical report covering (1) analysis of uranium bromide and chloride samples, (2) the ferric-nitrate method of analyzing uranium fluorides for fluorine, (3) spectrographic determination of boron, cadmium and manganese in magnesium metal, (4) service analyses. contributions to other problems, (5) attempted preparation of uranous oxyfluoride, and (6) corrections in previous reports.

Technical report. Quite pure anhydrous ThCl4 in small quantity (8-10 g charge) has been prepared by the action of a mixture of Cl2 and CCl4 vapor on ThO2 at 675 degrees to 725 degrees C.

Technical report with short reports on (1) Effect of radiation on organic compounds; (2) Effect of radiation on separation processes; (3) Effect of radiation on water and aqueous systems; and (4) Effect of neutrons on graphite.

Technical report. Photomicrographs showing the effect of heating polished uranium surface at 600, 700, 850, and 1000 degrees C, and sandblasted and cut surface at 1000 degrees C are included.

Abstract. The precipitation of Pa233 with MnO2 from a solution of thorium nitrate has been studied in some detail and seems quite satisfactory up to 36 gm Th(HO3)4 4H2O per 100 cc solution. The concentration of Pa233 with respect to the manganese dioxide carrier and the thorium precipitated with the carrier appears to be accomplished quite well by either a series of MnO2 cycles or thorium iodate cycles. Volatility methods for both the separation of Pa233 from the original thorium and for its separation from MnO2 are now under investigation. It has been decided that thorium carbonate will the the thorium compound used in the pile at Site X.

Abstract. Chemical analytical studies of graphite raw materials have revealed new sources of petroleum cokes and pitches of greater purity than those previously used in the manufacture of project graphite. The use of these raw materials of exceptional purity has resulted in an improvement in k of the order of one per cent as compared with the AGOT-AGNT graphite typical of the previous production. A study of the graphitizing process has shown that no dangerous impurities are introduced in the graphite in manufacture; rather, the process actually purifies. furthermore, impurities are distributed homogeneously within the furnace charge; thus the AGOT-AGNT distinction is no longer necessary. A comparison of the methods of graphite testing has demonstrated excellent correlations between chemical analytical data, the results of the function test at Argonne, and the sigma pile experiments. It may therefore be inferred that chemical testing should be an adequate control of the graphite purity. Methods are described for the analysis of ash, B, V, TI, FE, and Ca in petroleum coke, pitch, and graphite.

Technical report summarizing our knowledge of the chemical effects of ionizing radiation upon water and upon aqueous solutions of inorganic compounds. The types of radiation considered are beta rays, gamma and X rays, and heavy particles, notably neutrons, deuterons, alpha rays and fission recoils.

Technical report abstract: Since UNH is a highly dissociated compound which ionizes to NO3 and (UO2), the latter ion being very weakly basic, a solution of pure UNH is quite acid (pH about 3). It is possible to titrate to a phenolphthalein and point with standard caustic solution and obtain a figure which represents the free acid plus the NO3 from the the UNH. However, titration of the free nitric acid alone in such a solution presents quite a problem. By precipitating and removing uranium from solution by means of potassium ferrocyanide, the residual free acid may be titrated directly by means of standard caustic using either methyl red or phenolphthalein indicators, with an error of less than 4%. A method is given to determine formic acid, should that acid be present in the mixture.

Technical report. The object of the research is to determine the procedure and equipment for the preparation of U233 on a semi-works scale. The general proposed procedure is that thorium carbonate in aluminum cans will be irradiated with pile neutrons. The Pa233 resulting from neutron absorption the Th232 and the decay of Th233 will be extraction from 99% of the thorium and the natural U in thorium by MnO2 precipitations. The Pa233 will then be allowed to decay to U233 which in turn will be isolated from the remaining Th and partially decayed Pa233 by ether extraction.

Technical report. The effect of temperature during pile exposure on the fast-neutron-induced change in properties of graphite was studied. Temperatures up to 125 degrees C have no effect upon the rate of increase of elastic modulus; pieces exposed at 300 degrees C on the other hand show no change at all in elastic modulus. The increase in electrical resistance s an inverse function of the temperature of exposure at all temperatures in the range 60 to 300 degrees C.

Technical report abstract. The present state of knowledge concerning the effect of pile radiation on a variety of solid materials is reviewed. Radiation corrosion will not be a serious hazard for aluminum or stainless steel but it can be for iron or lead if either are exposed to water. Apart from corrosion the principal uncertainty is in regard to the Wigner effect on the behavior of metals. There is at present no ground for optimism regarding the behavior of tuballoy. The effect on aluminum or a bonding material while less severe must also be considered serious. The expectation in regard to graphite is that its behavior will not cause trouble during the first 100 days of operation although serious troubles will probably arise within two years of operation. Organic materials can be used safely only in regions of limited exposure.

Technical report with short articles on (1) Uranium-oxygen system compositions UO2 to U3O3; (2) Thorium hydride; (3) Production of cerium; and (4) Production of thorium.

Abstract: Pure UO2F2 is made by reaction between anhydrous HF and pure UO3. Although it is difficult to prepare free of water, it is not very hygroscopic. Prolonged heating at 100-105 degrees releases 99.9% of the water in an aqueous solution; the rate of loss of water is very small after saturation is reached. X-ray diffraction data give a density of 6.2 for the solid. The density of a 1.004 M solution is 1.274; the density of a saturated solution (5.130 M) is 2.400. The densities of F-9 solutions have been calculated from the densities of ordinary aqueous solutions, and the values are compared graphically. Data on the solubility indicate that there is a small increase in the range 25-100 degrees. Recovery of pure F-9 from a solution is hampered by hydrolysis of U)2F2 to give HF. The HF may be held back by addition of UO3 or CaO; the use of the latter, however, makes more difficult the recovery of all the F-9. Molar conductivities of UO2F2 solutions at 25 degrees, as well as the specific conductivities of a 1 molar solution containing various concentrations of UO3, have been determined. The addition of UO3 lowers the conductivity. The low …