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Relative Reaction Rates of Sulfamic Acid and Hydroxylamine with Nitric Acid

Description: This report describes a study of comparative reaction rates where the reductant is in excess, as in the 1B bank in the Purex process. The results of this work apply to planned plant tests to partially substitute HAN for the ferrous sulfamate reductant in the Purex 1B bank.
Date: March 28, 2001
Creator: Karraker, D.G.
Partner: UNT Libraries Government Documents Department

SELECTIVE REDUCTION OF PLUTONIUM(VI) TO PLUTONIUM(IV) IN A PLUTONIUM(IV-VI) NITRIC ACID SOLUTION

Description: The technique for adjusting the valence of Pu in the Pu(IV-VI) system to the Pa(IV) state for efficient solvent extraction or anion exchange is described. Investigations show that Pu(VI) may be reliably reduced to Pu(IV) with ferrous suifamate s. Nitric acid concentration must be between 2 and 6 M to avoid Pu disproportionation of suifamate precipitation. Ferrous sulfamate concentration is kept below 1 M to prevent crystal formation after the reaction, but Pu concentration may be as high as 250 g/l. (P.C.H.)
Date: February 1, 1961
Creator: Campbell, M.H.
Partner: UNT Libraries Government Documents Department

OXIDATION OF PLUTONIUM (III) BY SODIUM NITRITE

Description: The reaction velocity constant for the oxidation of Pu(III) by nitrite in HNO/sub 3/ solution containing ferrous sulfanate is given. The reaction rate was found to be measurable by means of spectrophotometry. The data indicate the reaction to be a pseudo first-order reaction in the region of HNO/sub 3/ and nitrite concentration of interest. The reaction velocity constant, expressed as a first-order reaction with respect to Pu, was found for several values of HNO/ sub 3/ and nitrite concentrations. The HNC/sub 3/ reaction velocity constant relationship is given. The oxidation of the ferrous sulfamate--Pu(III Pu(III) solution proceeds successively through the sulfamate, ferrous, and Pu(III) ions. An autocatalytic mechanism is asscciated with the oxidation of both ferrous and Pu ions which obviates the possibility of simple calculations of constants based on nitrite concentration. An empirical relationship between the reaction velociiy constant and the (added) nitrite concentration is given. (auth)
Date: July 17, 1957
Creator: Brunstad, A.
Partner: UNT Libraries Government Documents Department

URANIUM(IV) NITRATE AS A REDUCING AGENT FOR PLUTONIUM(IV) IN THE PUREX PROCESS

Description: Practical procedures were demonstrated for partitioning plutonium from uranium in the Purex process with hydrazine-stabilized uranium(IV) nitrate as the reducing reagent for plutonium. Typical partitioning results were 0.04--0.2% loss of plutonium to the uranium product and less than 1 wt% uranium in the plutonium product. With uranium(IV) nitrate as a replacement for ferrous sulfamate, most solids in wastes from the Parex process can be eliminated. No undue hazard is expected from the use of hydrazine as the stabilizing agent. (auth)
Date: April 1, 1963
Creator: Schlea, C.S.; Caverly, M.R.; Henry, H.E. & Jenkins, W.J.
Partner: UNT Libraries Government Documents Department

Concentration of Plutonium by Cation Exchange--Stabilization of Pu(III) in Nitric Acid

Description: A study to define the effectiveness limits of sulfamic acid and to discover other better stabilizers for Pu(III) is described. Ascorbic and isoascorbic acids, used in conjunction with sulfamic acid reduced Pu(IV) to stable Pu(III) in nitric acid. Aminoguanidine sulfate also retarded the oxidation of Pu(III) but did not reduce Pu(IV). (J.R.D.)
Date: February 1, 1959
Creator: Tober, F. W. & Russel, E. R.
Partner: UNT Libraries Government Documents Department

Decontamination solution development studies

Description: This study was conducted for the Westinghouse Hanford Company (WHC) by Pacific Northwest Laboratory (PNL) as part of the Hanford Grout Technology Program (HGTP). The objective of this study was to identify decontamination solutions capable of removing radioactive contaminants and grout from the Grout Treatment Facility (GTF) process equipment and to determine the impact of these solutions on equipment components and disposal options. The reference grout used in this study was prepared with simulated double-shell slurry feed (DSSF) and a dry blend consisting of 40 wt % limestone flour, 28 wt % blast furnace slag, 28 wt % fly ash, and 4 wt % type I/II Portland cement.
Date: September 1, 1993
Creator: Allen, R. P.; Fetrow, L. K.; Kjarmo, H. E. & Pool, K. H.
Partner: UNT Libraries Government Documents Department

Absorption Spectra of Plutonium and Impurity Ions in Nitric Acid Solution

Description: The absorption spectra for Pu(III), (IV), (VI), and the red Pu(IV)- peroxy complex were determined in HNO/sub 3/ solution. Extinction coefficients for the above species of Pu were measured. Temperature has little effect on the spectra, but variation of acidity causes shifting of absorption peaks and some changes in the extinction coefficients. The absorption spectra and extinction coefficients in the region 390 to 1200 m mu were measured for chromic, nickelous, manganous, calcium, lanthanum, aluminum, ferrous. ferric, and permanganate ions in HNO/sub 3/ solutions. In addition, the effects of nitrite, oxalic acid, sulfamic acid, hydrogen peroxide, and various HNO/sub 3/ concentrations on the extinction coefficients of some of these ions were determined. The chromic, nickelous, ferrous, and permanganate ions, and ferric ion with oxalic acid, have sufficiently high extinction coefficients to cause inaccuracies in valence determinations of Pu in solutions containing high concentrations of these ions, unless corrections are made. (auth)
Date: July 31, 1956
Creator: Myers, M. N.
Partner: UNT Libraries Government Documents Department

CONTROLLED-POTENTIAL COULOMETRIC TITRATION OF URANIUM(VI) IN THE PRESENCE OF NITRATE

Description: A study into the use of sulfamic acld as a nitritedestroying reagent in the controlled-potentlal coulometrlc tltratlon method for uranlum(VI) was made. When nltrites are thus destroyed, the tltration ls much less subject to error from HNO/sub 3/. The results of titratlons of known amounts of uranlum(VI) in the presence of varlous amounts of HNO/sub 3/, Th(NO/sub 3/)/sub 4/, Al(NO/sub 3/ )/sub 4/, and LiNO/sub 3/ are given. (auth)
Date: January 17, 1962
Creator: Shults, W.D.
Partner: UNT Libraries Government Documents Department

Kinetics of the ambient temperature dissolution of plutonium metal in sulfamic acid

Description: The stoichiometry and the kinetics of the ambient temperature dissolution of alpha-phase plutonium in sulfamic acid has been determined. Hydrogen off-gas rates and plutonium concentrations were calculated as functions of time for a variety of dissolving conditions. Calculations show that nominal 2.2 kg Pu buttons (surface area, 171 cm/sup 2/) should yield solutions containing 60 +- 10 g Pu/L after a one-hour dissolving cycle. Hydrogen off-gas rates were calculated to vary from as high as 780 mL of gaseous hydrogen per minute (STP) at the beginning of a dissolving cycle to as low as 150 mL H/sub 2/(g) per min near the end of a dissolving cycle.
Date: March 1, 1978
Creator: Gray, L.W.
Partner: UNT Libraries Government Documents Department

Radiolysis gases from nitric acid solutions containing HSA and HAN

Description: The concentration of hydrogen (H{sub 2}) in the radiolytically produced off-gas from 2.76-4.25M HNO{sub 3}/PU solutions has been found to be greatly reduced in the presence of sulfamic acid (HSA) and hydroxylamine nitrate (HAN). The H{sub 2} concentration ([H{sub 2}]) is reduced from 35 percent to about 4 percent by dilution caused from an increase in the production rates of nitrogen (N{sub 2}), nitrous oxide (N{sub 2}O), and oxygen (O{sub 2}) gases. The generation rate of H{sub 2} was not affected by HSA or HAN giving a measured radiolytic yield, G(H{sub 2}), value of 0.201 molecules/100 eV for 2.765M NO{sub 3}{sup -} solution (a value of 0.213 is predicted from previous data). The G(H{sub 2}) values are dependent on the solution nitrate concentration ([NO{sub 3}{sup -}]). The generation rates of N{sub 2}, N{sub 2}O, and O{sub 2} are not dependent on the [NO{sub 3}{sup -}] in this narrow range, but are dependent on the presence of HSA and the concentration of HAN. The percentage [H{sub 2}] for the 2.5 to 3.0M NO{sub 3}{sup -} range expected in the off- from the FB-Line Pu{sup +3} Hold Tanks is conservatively estimated to be about 3.5 to 4.5 % for Pu + 3 solutions initially containing 0.023M HAN/0.165M HSA. The upper limit [H{sub 2}] may actually be about 4.1 % (4.3 % at 90 % confidence limits) but more {open_quotes}initial{close_quotes} off-gas rate data is needed at about 2.9M [NO{sub 3}{sup -}] in Pu{sup +3} solution for verification. Addition of ascorbic acid had no effect on the off-gas rate of Pu{sup +3} solutions containing HSA and NO{sub 3}{sup -} concentrations higher than those expected in the hold tanks. The maximum {open_quotes}hold time{close_quotes} for 50 grams/liter Pu{sup +3}/0.165M HSA/0.023M HAN/2.5-3.0M HNO{sub 3} solution is 20.3{+-}2.1 days. After this time the HSA initially present will become ...
Date: October 28, 1994
Creator: Smith, J. R.
Partner: UNT Libraries Government Documents Department

CONCENTRATION AND FINAL PURIFICATION OF NEPTUNIUM BY ANION EXCHANGE

Description: It was demonstrated that neptunium(IV) can be readily absorbed onto anion exchange resins from 6 M HNOsub 3/ containing ferrous sulfamate and hydrazine or semicarbazide, separated from plutonium, uranium, and common metallic impurities by washing the resin at 25 deg C with 6 M HNO/sub 3/ containing ferrous sulfamate and hydrazine or semicarbazide, separated from fission products and thorium by washing the resin at 60 deg C with S M HNO/sub 3/- 0.01 M HF containing hydrazine or semicarbazide, and eluted at concentrations greater than 40 g Np/l with 0.35 M HNO/sub 3/ at 25 deg C. Decontamination factors of greater than 10,000 from uranium, plutonium, and common metallic contammants, greater than 25,000 for fission products normally expected in the feed (mainly Zr-Nb with some Ru-Rh), and greater than 1000 for thoriuin are obtainable under proper operating conditions. Because of the low processing rates, the necessity for carrying out the absorption cycle at 25 deg C and the absence of radiation daraage problems, Dowex 1, X-4 (50-100 mesh) or Dowex 21K (50-100 mesh) resins are considered the best choices for this application. Gassing occurs with the use of ferrous sulfamate - semicarbazide reductant but is not a serious problem and does not occur with ferrous sulfamate -hydrazine reductant in 6 M HNO/sub 3/. (auth)
Date: February 10, 1959
Creator: Ryan, J. L.
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

Purex Process Performance With Short-Residence Contactors

Description: Recovery and purification were satisfactory in miniatarepilot-plant tests of the Purex first cycle with the solvent residing four seconds in each extraction stage. Decontamination factors for both zirconium-- niobium and ruthenium were greater than 10,000 with negligible crosscontamination of uranium and plutonium. The effects of the following on decontamination and plutonium partitioning were determined: irradiation level of the fuel, operating temperature, solvent saturation, accumulated exposure of the solvent, nitrous acid, and ferrous sulfamate versus U(IV) as a reductant for Pu(IV). (auth)
Date: September 1, 1963
Creator: Schlea, C. S.; Caverly, M. R.; Henry, H. E. & Jenkins, W. J.
Partner: UNT Libraries Government Documents Department

Nonnuclear consolidation weapons production support project for the Kansas City Plant

Description: The US Department of Energy (DOE) has prepared this Environmental Assessment (EA) to assist the agency in complying with the National Environmental Policy Act (NEPA) of 1969 as it applies to a Nonnuclear Consolidation Weapons Production Support Project (the project) that uses an electrochemical etching process at the DOE`s Kansas City Plant (KCP). The project is expected to last approximately five years. This action is needed to support continued reconfiguration of the Nonnuclear Weapons Complex. AU elements of the reassigned project, except electrochemical etching of solid depleted uranium (DU) components, have been performed at the KCP for several years and are considered ongoing and continuing operations in support of the plant`s mission. The proposed action includes renovation of an existing building at the KCP to accommodate equipment, security and environmental controls, and building restoration upon project completion, including disposal of equipment and wastes. The electrochemical etching process will use a sulfamic acid bath which will be designed to include environmental controls that prevent impact to the environment. Low-level waste (LLW) and mixed wastes will be generated by the electrochemical etching process. No liquid effluents or air emissions are anticipated as a result of this process. Pollution prevention practices will be aggressively utilized to reduce the quantity of wastes generated as a result of this work. The no-action alternative is to continue current operations without assignment of the electrochemical etching process to the KCP.
Date: December 1, 1995
Partner: UNT Libraries Government Documents Department

Removal of sulfamic acid from plutonium sulfamate--sulfamic acid solution

Description: Plutonium metal can be readily dissolved in aqueous solutions of sulfamic acid. When the plutonium sulfamate--sulfamic acid solutions are added to normal purex process streams, the sulfamate ion is oxidized by addition of sodium nitrite. This generates sodium sulfate which must be stored as radioactive waste. When recovery of ingrown /sup 241/Am or storage of the dissolved plutonium must be considered, the sulfamate ion poses major and undesirable precipitation problems in the process streams. The present studies show that 40 to 80% of the sulfamate present in the dissolver solutions can be removed by precipitation as sulfamic acid by the addition of concentrated nitric acid. Addition of 64% nitric acid allows precipitation of 40 to 50% of the sulfamate; addition of 72% nitric acid allows precipitation of 50 to 60% of the sulfamate. If the solutions are chilled, additional sulfamic acid will precipitate. If the solutions are chilled to -10/sup 0/C, about 70 to 80% of the orginal sulfamic acid in the dissolver will precipitate. A single, low-volume wash of the sulfamic acid crystals with concentrated nitric acid will decontaminate the crystals to a plutonium content of <10/sup 5/ dis/(min-gram) (approx./sup 2/..mu..g Pu/g sulfamic acid).
Date: October 1, 1978
Creator: Gray, L.W.
Partner: UNT Libraries Government Documents Department