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Description: A process for separating americium and curium from rare earths by anion exchange based on selective chloride complexing was developed and tested on a laboratory scale. The separation is accomplished by sorption of americium, curium, and rare earths on Dowex 1-10X resin from a solution of 8 M LiNO/dub 3/ followed by selective elution of rare earths with 10 M LiCl and americium-curium elution with 1 M LiCl. In a laboratory demonstration of this process, greater than 99.5% of americium tracer containing no detectable amounts of rare earths was recovered. (auth)
Date: June 1, 1960
Creator: Loyd, M.H. & Leuze, R.E.
Partner: UNT Libraries Government Documents Department

The Magnesium-28-Aluminum-28 System: An Aluminum-28 Generator

Description: A milking method was developed for the production of the short-lived Al/ sup 28/ for use in physiological experiments. A Mg/sup 28/ solution is obtained by the irradiation and purification of a Li/sup 6/Mg/sup 26/ alloy, and it is placed on a Dowex 50W column in the Na/sup +/ form and then washed with 1 N NaOH. The Al/sup 28/ is eluted in 10 to 30 sec by 1 N NaOH solution containing 0.5 mg/ ml of carrier Al. The half lives of Mg/sup 28/ and Al/sup 28/ were determined to be 20.88 plus or minus 0.06 hr and 2.238 plus or minus 0.006 min, respectively. (D.L.C.)
Date: March 15, 1963
Creator: Weiss, A. J. & Hillman, M.
Partner: UNT Libraries Government Documents Department

Uranium Anion Exchange Equilibria on Dowex 21K

Description: Equilibrium loading of uranium on Dowex 21K was studied in a sulfate system for uranium concentrations from 0.0005 to 0.005M, total sulfate concentrations of 0.045 to 0.6M, and sulfuric acid concentration of 0.020M. Loading data were fitted to Langmuir adsorption isotherms and Langmuir constants were evaluated. Resin was equilibrated with uranium feed solutions by flowing the feed through a shallow fixed bed of resin. (auth)
Date: June 29, 1959
Creator: Dunn, W. E.
Partner: UNT Libraries Government Documents Department


Description: Tungsten and graphite are unsuitable materials of construction for a UF/ sub 6/ inlet nozzle in a continuous DRUHM reactor. Preparation of feed was completed for an extended Fluorox test. Difficulties were experienced in the operation of a fluidized bed TbNT denitrator. Flame denitration of UNH and TbNO produced mixed oxides of 1 to 14 micron mean particle size. The chloride capacity of Dowex 21K was measured, and equilibria measurements of uranium sorption from sulfate solutions were continued. Siliceous deposits in the stripping column caused the termination of a Darex run with a prototype APPR fuel element. Hot runs were begun on the chemical dejacketing of irradiated PWR blanket pins. The addition of formaldehyde to neutralize "25" waste reduced the recovery of nitrate from the calciner off-gas from 76% to 23%. (For preceding report see CF-58-9-62.) (auth)
Date: December 19, 1958
Creator: Bresee, J.C.; Haas, P.A.; Watson, C.D. & Whatley, M.E.
Partner: UNT Libraries Government Documents Department


Description: ABS>Uranium metal is produced by the bomb reduction of UF/sub 4/ with Mg. The slag from this reduction contains appreciable quantities of U, either in the metallic or the tetrafluoride form, in addition to the MgF/sub 2/. A process for recovering low enrichmeat U from this slag has gone into operation. A study of the causes of resin attrition and their relative magnitude both from an over-all point of view and with specific reference to the Higgins' Column and Dowex 21K resin is preseated. Equipment was designed, assembled, and tested to investigate the effects of valve action, wall to resin and resin to resin friction, repeated chemical cycling, and column height. Certain mechanical properties of the resin beads were investigated, and some existing plant data were analyzed. A discussion of the probable mechanism of attrition and its contribution to the overall amount of attrition is presented. (W.L.H.)
Date: April 1, 1958
Creator: Seiler, G.R.; Ammann, P.R. & Newey, A.B.
Partner: UNT Libraries Government Documents Department

Sequential Separation of Some Actinide Elements by Anion Exchange

Description: Methods are presented by which trace amounts of several actinide elements are separated. Use is made of the large differences in distribution coefficients, so careful chromatographic techniques are not necessary. Small columns are used, allowing the desired constituent to be obtained in 10 ml or less. One method is used to separate americium, plutonium, and neptunium. These elements are sequentially eluted from columns of Dowex 1 resin in that order by 8 M HNO/sub 3/, 0.02 M ferrous sulfamate in 4.5 M HNO/sub 3/, and 0.001 M ceric sulfate in 0.25 M HNO/sub 3/. Another method is used to separate americium, thorium, plutonium, and neptunium sequentially in that order by S M HNO/sub 3/, 12 M HCl, 12 M HCL--0.1 M NH/sub 4/I, and 4 M HCL by elutriation. Protactinium and uranium follow the americium in both methods. The methods presented are characterized by a low degree of cross contsmnination. Yields are greater than 95 percent. (auth)
Date: June 1, 1959
Creator: Roberts, F. P. & Brauer, F. P.
Partner: UNT Libraries Government Documents Department


Description: A study of the equiibrium sorption isotherms and rates of U sorption on Dowex 21K is in progress. Data which show the effects of uranium concentration in solution on resin loading are presented Fuel reprocessing experiments are reported in which efforts were made to reduce Cl- in Darex dissolver solution to < 350 ppm for the extraction phase. The best method of Cl/sup -/ reduction appears to be operation with a down draft condenser and an air sparge. A check- out dissolution min in the 6 in. glass dissolver with a prototype APPR fuel element is reported, and data on dissolution time and composition of reacted products are given. Data on filtration rates for Darex solutions expected in large-scale operations are tabulated, and graphs illustrating the effects of pressure drop and filter aids on filtering rates are presented. Tests on washing U from filter cakes indicate that U can be removed to any desired level. Viscosity, density. and boiling points as a function of temperature or pressure were determined for two Darex solvent extraction feed solutions; data are presented grahically, and results of chemical analyses are tabuated. Demonstation runs for Sulfex and Zirflex dejacketing flowsheets were made. Results indicate that parts of the Sulfex flowsheet map have to be changed to prevent core losses from fluoride contamination. Results from the Zirflex demonstration are being compiled. Design of the SRE decanning device was completed and sub mitted to vendors for bids; also the design of a prototype fuel bundle to serve as an inexpensive substitute in chopping and leaching studies is reported. Preliminary shearing studies with the 120 ton hydraulic Manco shear indicate that its usefulness is limited, and criteria for a large shear for spent fuel bundles are being written. Darex-type solvent extraction studies using hexane are reported, and U ...
Date: May 1, 1959
Creator: Shank, E M
Partner: UNT Libraries Government Documents Department


Description: An effort is being made to determine the equilibrium sorption isotherms and rates of sorption of U on the anion exchange resin Dowex 21K. In the Darex process investigations included: batchwise Cl/sup -/ removal and feed adjustment, continuous dissolution, feed clarification, filtration rates for solutions, effect of pressure drop and fllter aid on flltration rate, cake washing and removal, properties of solutions, and properties of sands and filter aids. Batch dissolutions of irradiated' Consolidated Edison Fuel and PWR blanket pins were made to demonstrate the Sulfex and Zirflex dejacketing flowsheets, respectively. Dissolution studies to obtain rate and penetration data for UO/sub 2/ in HNO/sub 3/ solutions were begun. Preliminary shearing studies with the 120 ton hydraulic Manco shear with a prototype fuel bundle showed that a line contact shear closes the fuel bearing tubes to an extent detrimental to good leaching. A series or experiments was performed to determine the amount of fission products evolved when different types of wastes were dried and calcined. (W.L.H.)
Date: May 1, 1959
Creator: Shank, E M
Partner: UNT Libraries Government Documents Department


Description: A critical review of the literature revealed no experiments on uranyl ion transfer from an aqueous to a tributyl phosphate phase which positively measured the kinetics of the chemical reaction at the interphase. Drawing isorhythmic lines on a three component diagram gives a complex correlation for the compaction of three sizes of glass beads. Neither the use of thoria sols nor high feed solution concentrations of thorium nitrate gave any significant increase in mean particle diameters over those obtained from nitrate solutions of lower concentrations in flame denitration. A hydraulic film resistance has been detected in the anion exchange of uranyl sulfate into Dowex 2lK, and chloride elution was found to give a higher apparent uranium diffusion coefficient than nitrate elution. The rate of dissolution of mixed thorium-uranium oxides was determined as a function of the per cent of mixed oxides dissolved. Mixing in tanks packed with boron glass Raschig rings is being continued. The SRE hydraulic dejacketer has been operated successfully with prototype fuel rods. Excessive foaming was encountered when sheared stainless-clad UO/sub 2/ was suddenly contacted with boiling 13 M nitric acid. While attempting to shear a prototype Yankee subassembly with Kanigan brazed diffusion bonded joints, a five tube aggregate was formed at one of the two ferrule locations sheared. Of the 91 protective coatings exposed to ionizing radiation from the HRE, 25 of the coatings outside of the shield and 10 coatings inside the shield exhibited satisfactory resistance. HETS values in the acid Thorex flowsheet are reported. Waste calcination of simulated Purex waste in a 7-in.-diameter vessel gave rates slightly higher than predicted by the radial deposition model because of loss of feed due to excess foaming. (For preceding period see CF-60-6-11.) (auth)
Date: October 27, 1960
Creator: Whatley, M E; Haas, P A; Horton, R W; Ryon, A D; Suddath, J C & Watson, C D
Partner: UNT Libraries Government Documents Department


Description: 8 7 6 2 ; 7 4 7 6 : 7 8 : : ; half life of 3.781 plus or minus 0.010 years based on calorimetric measuiements. The calorimetric assay of the sample will be continued ior several years to decrease the probable error. The decay scheme for /sup 209/Po--/sup 209/Po/ isitopic mixtures is being determined. The gamma spectrum is being studied using two sources of different isotopic composition. Definite peaks were established at 76, 260, 300, 575, and 9l0 kev. Various multiple coincidence experiments indicated that the 300- and 575-kev photons and the 76-kev x-ray are in triple coincidence. Relative intensities of the various gamma rays from the two different sources indicated that the 575-kev photon is associated with /sup 208/ Po decay, while the 260- and 910-kev states are attributed to /sup 209/Po. A theoretical estimate of the partial alpha half life for /sup 208/Po decay to the 2+ level in /sup 204/Pb (at 0.899 Mev) was made. This value (2.5 x 10/sup 6/ years) was determined graphically by extrapolation to an alpha particle energy of 4.2l1 Mev. /sup 209/Po--/sup 2o9/Po sources are being prepared for the investigation of the internal conversion electron spectra of these isotopes. Ion exchange techniques are being studied for the separation of /sup 227/Ac from / sup 227/Th, /sup 223/R a, and /sup 226/Ra. Naturally occurring lanthanum, thorium, and barium are being used as experimental substitutes. Composite elution curves indicated that lanthanum and /sup 232/Th can be successfully isolated with 2 M HCl, 3 M HNO/sub 3/, and ammonium acetate as elutrients. A purified form of the original Dowex 50W-X8 column packing matenial was used; the new material (AG-50W-X8) reduced tailing on the elution curves. /sup 228/Th was tentatively assigned a half life of 1.9132 years with an internal probable error of ...
Date: July 30, 1963
Creator: Eichelberger, J.F.; Grove, G.R. & Jones, L.V.
Partner: UNT Libraries Government Documents Department

Progress Report No. 52 for December 1, 1957 Through February 28, 1958

Description: Some approximate values of the concentrations of the chlorine ion and the mean activity coefficients of HCl in Dowex 50, as functions of the mean activity of HCl are given. The KCl uptake by anion-exchange resins, Dowex 1 and 2, is plotted. Ion-exchange phase properties of HCl were determined from freezing point measurements. The thermodynamic acid dissociation constants of HClO/sub 4/, HCl, HNO/sub 3/, HBr, and HGaCl/sub 4/ in water-saturated bis(2- chloroethyl) ether, were obtained from couductometric measurements. The distribution behavior of InBr/sub 3/ and IuCl/sub 3/ in HBr and HCl was studied. Information is given on the extraction of Zn and Ag from chloride solutions by dioctylamine salts. Ion exchange equilibria between hexammino-cobalt(III) and chloro-pentammino-cobalt(In ions in respect to La ions in Dowex 50 NaR are plotted. Typical radiochemical activation analyses for K in geologic materials are tabulated. The postulated nuclear level scheme and the calculiated and experimental positron decay following ( gamma ,n) activation of Br/sup 79/ are shown for Br/sup 78/. Cumulative fission yields in the deuteron fission of U/sup 235/ are tabulated. Cosmic ray data obtained with a new highcounting rate meson monitor are plotted. The equipment used and data obtained in a search for long- lived particles with mass ~ 550m/sub e/ in the cosmic-ray flux at sea level are shown. The excited states of Ni/sup 58/ and Ni/sup 61/ obtained from (d,p) reactions of Ni/sup 58/ and Ni/sup 60/ are tabulated. (For preceding period see AECU-3685.) (M.H.R.)
Date: February 28, 1958
Partner: UNT Libraries Government Documents Department


Description: Thoria denitrator products from 0.04 to 0.066 N/Th ratio were dispersed into sols at N/Th radios of 0.11 to 0.19 and processed by the sol-gel technique to produce final compacted thoria products with little significant variation. Experimental results of H/sub 2/-CuO reaction in the helium purification work further substantiated the mathematical model. The elutions of uranyl sulfate loaded Dowex 2lK with chloride apparently involved the diffusion of both the sulfate ions and the uranyl ions. The dejacketing of the NaK bonded SRE Core I fuel elements is proceeding satisfactorily with an average rate that has increased to 7 to 8 kg U/hr. The uranium slugs exhibited various degrees of camber and pitting. The disintegration-leaching of 3% U-graphite fuel by flowing 90% HNO/sub 3/ at 60 deg C is apparently superior to a batch-leach method. Attempts to use air bubblers to control the interface level at the bottom of a 2- in.-dia glass pulse column showed considerable loss of pulse amplitude, particularly in taller columns. An air operated diaphragm pump was designed, fabricated, and tested for use as a TrU facility process pump. A successful duplicate test was made calcining TBP-25 waste using the close coupled evaporator- calciner system. (auth)
Date: January 30, 1962
Creator: Whatley, M.E.; Haas, P.A.; Horton, R.W.; Ryon, A.D.; Suddath, J.C. & Watson, C.D.
Partner: UNT Libraries Government Documents Department