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A Rapid Method for Determination of Water in TO₃

Description: Summary: A set of conditions is described for a ten minute determination of water in TO₃ by ignition and absorption of the evolved water in magnesium perchlorate. Complete conversion to T₃O₃ is obtained under these conditions, so that total loss on ignition and total T (plus non-volatile impurity) content may also be obtained. It has been found unnecessary to employ Cu foil to prevent interference by nitrates, which may be present with a nitrate/water ratio as high as 5, and in an amount that does not exceed 100 mg.
Date: February 16, 1945
Creator: Barash, Bernard B.; Lee, Franklin B. & Curtiss, Edgar O.
Partner: UNT Libraries Government Documents Department

The Reduction of Uranium Trioxide by Ethyl Alcohol

Description: Abstract: The effect of temperature upon the rate of reduction of uranium trioxide by ethyl alcohol has been investigated, and a comparison of the reactivity of the dioxide produced at various temperatures has been made. The percent of carbon in the end product has been studied with respect to both temperature of reduction and length of exposure to alcohol. Optimum conditions for the reduction have been suggested.
Date: November 18, 1946
Creator: Haines, B. M. & Calkins, V. P.
Partner: UNT Libraries Government Documents Department

Thermal decomposition of UO{sub 3}-2H{sub 2}0

Description: The first part of the report summarizes the literature data regarding the uranium trioxide water system. In the second part, the experimental aspects are presented. An experimental program has been set up to determine the steps and species involved in decomposition of uranium oxide di-hydrate. Particular attention has been paid to determine both loss of free water (moisture in the fuel) and loss of chemically bound water (decomposition of hydrates). The influence of water pressure on decomposition has been taken into account.
Date: February 26, 1998
Creator: Flament, T.A.
Partner: UNT Libraries Government Documents Department

PROCESS ENGINEERING REPORT ON REVISED PROCESS DESIGN TRANSMITTAL, GREEN SALT PLANT, JOB NO. 3004 OF THE FEED MATERIALS PRODUCTION CENTER, FERNALD, OHIO. Specifications Contract No. 3000, Part XXV, Section 4

Description: Process design information concerning equipment and operation of a plant to produce UF/sub 4/ from UO/sub 3/ is presented. Included are process flow diagrams, drawings of ventilation and dust control systems, and vent gas systenas. Equipment lists and estimated utilities are also included as well as a description of the process. (J.R.D.)
Date: June 1, 1952
Creator: Holby, G.V. & James, F.
Partner: UNT Libraries Government Documents Department

AVLIS modified direct denitration: UO{sub 3} powder evaluation

Description: The evaluation study demonstrated that AVLIS-enriched uranium converted to UO{sub 3} can be used to prepare UO{sub 3} pellets having densities in the range required for commercial power reactor fuel. Specifically, the program has demonstrated that MDD (Modified Direct Denitration)-derived UO{sub 2} powders can be reduced to sinterable UO{sub 2} powder using reduction techniques that allow control of the final powder characteristics; the resulting UO{sub 2} powders can be processed/sintered using standard powder preparation and pellet fabrication techniques to yield pellets with densities greater than 96% TD; pellet microstructures appear similar to those of power reactor fuel, and because of the high final pellet densities, it is expected that they would remain stable during in-reactor operation; the results of the present study confirm the results of a similar study carried out in 1982 (Davis and Griffin 1992). The laboratory processes were selected on the basis that they could be scaled up to standard commercial fuel processing. However, larger scale testing may be required to establish techniques compatible with commercial fuel fabrication techniques.
Date: February 1, 1994
Creator: Slagle, O.D.; Davis, N.C. & Parchen, L.J.
Partner: UNT Libraries Government Documents Department

SEPARATION OF TECHNETIUM-99 FROM URANIUM HEXAFLUORIDE

Description: A system is described for recovery of Tc from UF/sub 6/ in a UO/sub 3/ fluorination plant. The Tc is retained on MgF/sub 2/ in traps through which the UF/sub 6/ stream is passed. The system is in operation at the Paducah Gaseous Diffusion Plant. (J.R.D.)
Date: January 1, 1963
Creator: Golliher, W.R.; LeDoux, R.A.; Bernstein, S. & Smith, V.A.
Partner: UNT Libraries Government Documents Department

The Use of a Fluidized Bed Reactor for the Continuous Production of Uranium Trioxide

Description: A program for development of a low-cost continuous process to produce uniform uranium trioxide from uranyl nitrate solution is described. A fluid bed reactor was developed and demonstrated for this purpose. Internal heat transfer tubes occupying one-third of the reactor cross section allowed for a production rate of 300 pounds of UC/sub 3//hr/ft/sup 2/ of bed cross section. It is felt that direct scale-up is feasible. UO/sub 3/ chemical purity was excellent and its physical properties could be controlled by variation of operating conditions. (J.R.D.)
Date: January 1, 1960
Creator: Philoon, W. C.; Sanders, E. F. & Trask, W. T.
Partner: UNT Libraries Government Documents Department

Investigation of Uranium Polymorphs

Description: The UO3-water system is complex and has not been fully characterized, even though these species are common throughout the nuclear fuel cycle. As an example, most production schemes for UO3 result in a mixture of up to six or more different polymorphic phases, and small differences in these conditions will affect phase genesis that ultimately result in measureable changes to the end product. As a result, this feature of the UO3-water system may be useful as a means for determining process history. This research effort attempts to better characterize the UO3-water system with a variety of optical techniques for the purpose of developing some predictive capability for estimating process history in polymorphic phases of unknown origin. Three commercially relevant preparation methods for the production of UO3 were explored. Previously unreported low temperature routes to β- and γ-UO3 were discovered. Raman and fluorescence spectroscopic libraries were established for pure and mixed polymorphic forms of UO3 in addition to the common hydrolysis products of UO3. An advantage of the sensitivity of optical fluorescence microscopy over XRD has been demonstrated. Preliminary aging studies of the α and γ forms of UO3 have been conducted. In addition, development of a 3-D phase field model used to predict phase genesis of the system was initiated. Thermodynamic and structural constants that will feed the model have been gathered from the literature for most of the UO3 polymorphic phases.
Date: August 1, 2011
Creator: Sweet, Lucas E.; Henager, Charles H.; Hu, Shenyang Y.; Johnson, Timothy J.; Meier, David E.; Peper, Shane M. et al.
Partner: UNT Libraries Government Documents Department

PREPARATION AND CHARACTERIZATION OF THE POLYMORPHS OF UO$sub 3$

Description: Six polymorphs of UO/sup 3/ were prepared and were identified by x-ray diffraction techniques. Differential thermal techniques were used to study the decompositions of the polymorphs to U/sub 3/O/sub 8/ and to investigate the modes of formation of the polymorphs from the hydrates of UO/sub 3/. (auth)
Date: August 1, 1962
Creator: Cornman, W.R. Jr.
Partner: UNT Libraries Government Documents Department

Summary of the Preliminary Analysis of Savannah River Depleted Uranium Trioxide

Description: This report summarizes a preliminary special analysis of the Savannah River Depleted Uranium Trioxide waste stream (SVRSURANIUM03, Revision 2). The analysis is considered preliminary because a final waste profile has not been submitted for review. The special analysis is performed to determine the acceptability of the waste stream for shallow land burial at the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada National Security Site (NNSS). The Savannah River Depleted Uranium Trioxide waste stream requires a special analysis because the waste stream’s sum of fractions exceeds one. The 99Tc activity concentration is 98 percent of the NNSS Waste Acceptance Criteria and the largest single contributor to the sum of fractions.
Date: October 13, 2010
Creator: National Security Technologies, LLC
Partner: UNT Libraries Government Documents Department

Summary of the Special Analysis of Savannah River Depleted Uranium Trioxide Demonstrating the Before and After Impacts on the DOE Order 435.1 Performance Objective and the Peak Dose

Description: This report summarizes the special analysis (SA) of the Savannah River Depleted Uranium Trioxide waste stream (SVRSURANIUM03, Revision 1) demonstrating the before and after impacts of the waste stream to the DOE Order 435.1 performance objective at the disposal facility, and the peak dose. The Nevada Division of Environmental Protection (NDEP) requested this SA and asked the Nevada Site Office (NSO) to run the SA deterministically and assume that all the model conditions remain the same regardless of the length of time to the peak dose. Although the NDEP accepts that DOE Order 435.1 requires a compliance period of 1,000 years, it also requested to know what year, if any, the specific DOE performance objectives will be exceeded. Given the NDEP’s requested model conditions, the SA demonstrates the Rn-222 peak dose will occur in about 2 million years and will exceed the performance objective in about 6,000 years. The 0.25 mSv y-1 all-pathway performance objective was not exceeded for the resident scenario after reaching the 4 million year peak dose.
Date: January 15, 2011
Creator: Shott, G.J.
Partner: UNT Libraries Government Documents Department

Calculational note for the radiological and toxicological effects of a UO{sub 3} release from the T-hopper storage pad

Description: UO{sub 3} powder is stored at the T-hopper storage area associated with the 2714-U building in the 200 west area. The T-hopper containers and 13 drums containing this material are used to store the powder on pads immediately north of the building. An interim safety basis document (WHC,1996) was issued in 1996 for the UO{sub 3} powder storage area. In this document the isotope {sup 99}Tc was not included in the source term used to calculate the radiological consequences of a postulated release of the powder. A calculations note (HNF, 1998) was issued to remedy that deficiency. The present document is a revision to that document to reflect updated data concerning the solubility of UO{sub 3} in simulated lung fluid and to utilize more realistic powder release fractions.
Date: June 18, 1998
Creator: Goldberg, H. J.
Partner: UNT Libraries Government Documents Department

Calculational note for the radiological effects of a UO{sub 3} release from the T-hopper storage pad

Description: UO{sub 3} powder is stored at the T-hopper storage area associated with the 2714-U building in the 200 west area. The T-hopper containers and 13 drums containing this material are used to store the powder on pads immediately north of the building. An interim safety basis document (WHC,1996) was issued in 1996. In this document the isotope{sup 99}Tc was not included in the source term used to calculate the radiological consequences of a postulated release of the powder. This calculational note is intended to remedy that deficiency. Input Data and Assumptions indicate that there is a total of 669,045 kg of uranium at the facility that is at risk for release to the atmosphere. Since uranium comprises 83.217 wt% of UO{sub 3}, this represents a little over 804 tonnes of powder. The postulated accident scenario is that 0.001 of the material at risk is released to the atmosphere.
Date: January 27, 1998
Creator: Goldberg, H.J.
Partner: UNT Libraries Government Documents Department

PUREX/UO{sub 3} facilities deactivation lessons learned history

Description: The Plutonium-Uranium Extraction (PUREX) Facility operated from 1956-1972, from 1983-1988, and briefly during 1989-1990 to produce for national defense at the Hanford Site in Washington State. The Uranium Trioxide (UO{sub 3}) Facility operated at the Hanford Site from 1952-1972, 1984-1988, and briefly in 1993. Both plants were ordered to permanent shutdown by the U.S. Department of Energy (DOE) in December 1992, thus initiating their deactivation phase. Deactivation is that portion of a facility`s life cycle that occurs between operations and final decontamination and decommissioning (D&D). This document details the history of events, and the lessons learned, from the time of the PUREX Stabilization Campaign in 1989-1990, through the end of the first full fiscal year (FY) of the deactivation project (September 30, 1994).
Date: January 1, 1995
Creator: Hamrick, D.G. & Gerber, M.S.
Partner: UNT Libraries Government Documents Department

THE REFLECTIVITY OF ORANGE OXIDES

Description: One of the basic problems associated with the production of uranium tetrafluoride is the varying reactivity of uranium trioxide (orange oxide). Separate batches of material produced by the same method may be so dissimilar that they require different sets of reaction conditions for satisfactory processing. Orange oxide (UO/sub 3/) is almost invariably a mixture of several different types. Reactivity'' is the term applied to the behavior or a given orange oxide with respect to its reduction to UO/sub 2/ and subsequent hydrofluorination to Uf/sub 4/. Assuming constant reaction conditions, it is thought that the reactivity of an orange oxide depends to varying degrees on the chemical composition and the physical makeup of the oxide. The visual examination of numerous samples of UO/sub 3/ suggested that the color of the oxide could be directly related to some of its chemical and physical properties. From this it was deduced that color ought to be related to the reactivity or the oxide and if so its measurement would permit the desired rapid prediction of reactivity. Quantitative measurements of color were made in the visible region of the spectrum. These measurements were compared to experimentally determined reactivities. A simple rapid test was ultimately devised for predicting the relative reactivity of any given sample of UO/sub 3/. The method requires only two to four measurements of reflectivity and can be completed in 15 minutes. (A.C.)
Date: November 15, 1957
Creator: Swinehart, B.A.
Partner: UNT Libraries Government Documents Department

FLUIDIZED-BED PROCESS FOR THE PRODUCTION OF URANIUM TETRAFLUORIDE (GREEN SALT) FROM URANYL NITRATE. Interim Report

Description: A proposed new processing technique for the production of uranium tetrafluoride from uranyl nitrate solution is described. This technique involves the application of the fluidized-bod principle for the contacting of gases with powdered solids. A new application of fluidization developed at this Laboratory and applied to the denitration of uranyl nitrate to produce uranium trioxide is also described. The purpose of this work is to develop a low-cost, continuous process for the denitration of uranyl nitrate hexahydrate, the reduction of uranium trioxide to uranium dioxide, and the hydrofluorination of uranium dioxide to uranium tetrafluoride. Uranium trioxide and uranium dioxide powders can be satisfactorily fluidized over a wide range of particle sizes. The product is a powder having a high bulk density and satisfactory physical and chemioal properties. Production rates of 100 Ib/hr/ft/sup 2/ of reactor cross section were demonstrated. Experimental work is continuing to obtain additional information of the effects of operating variables. Experimental work is now underway to determine the optimum hydrofluorination operating oonditions and to estimate the size and number of stages required for the production of specification-grade uranium tetrafluoride. (auth)
Date: December 30, 1954
Creator: Jonke, A.A.; Levitz, N.M.; Petkus, E.J. & Taecker, R.G.
Partner: UNT Libraries Government Documents Department