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Redox behavior below 1000K of Pt-impregnated CeO{sub 2}-ZrO{sub 2} solid solutions : an in-situ neutron diffraction study.

Description: The Ce{sup 3+} {leftrightarrow} Ce{sup 4+} redox process in automotive three-way catalysts such as Ce-ZrO{sub 2}/Pt provides an essential mechanism to oxygen storage/release under dynamic air-to-fuel ratio cycling. Such a function requires a metal-support interaction which is not completely understood. We have carried out an in-situ neutron powder diffraction study to monitor the crystal structures (a mixture of a major tetragonal and a minor monoclinic phase) of 10mol% Ce-doped ZrO{sub 2} with and without Pt (1wt%) impregnation under oxidizing and reducing conditions over the temperature range of 25--7000 C. The samples were heated first in flowing 2%O{sub 2}/Ar from room temperature to 400 C and then in 1%CO/Ar to about 700 C. A discontinued increase of the tetragonal unit-cell volume, a decrease of tetragonality (c/a), and a change of color from light yellow to gray when changing from oxidizing to reducing atmosphere were observed only in the sample containing Pt. This result supports the model which assumes the formation of oxygen vacancies initially near the Pt atoms. As more Ce ions are reduced from 4+ to 3+ oxidation states at high temperatures, oxygen vacancies migrate to the bulk of the oxide particles.
Date: January 12, 1998
Creator: Loong, C.-K.; Short, S. M.; Ozawa, M. & Suzuki, S.
Partner: UNT Libraries Government Documents Department

Material balance flowsheet Redox Production plant

Description: The attached material balance flowsheet for the proposed Redox Production plant is based on the two chemical flowsheets submitted by R.B. Richards of the Technical Division in HW 13,320 (INDC-3130) and HW 13,452 (INDC 3176). Production rates for the plant have been assumed as 2.5 short tone U per day (including a maximum of 0.75 short tons of U from stored Bi PO{sub 4} waste) and 19 kg. Pu per month (633 gms/day) as established by the Redox Committee. The flowsheets for preparation of solvent extraction feed from Bi PO{sub 4} waste, as well as the waste treatment systems will be covered in a future document.
Date: June 6, 1949
Creator: Tomlinson, R.E.
Partner: UNT Libraries Government Documents Department

Recovery of uranium and plutonium from Redox off-standard aqueous waste streams

Description: In the operation of countercurrent extraction columns as in the Redox process, it is possible, and probable, that from unexpected behaviour of a column, operator error, colloid formation, etc., there will result from time to time excessive losses of uranium and plutonium in the overall process. These losses will naturally accumulate in the waste streams, particularly in the aqueous waste streams. If the loss is excessively high, and such lost material can be recovered by some additional method, then if economical and within reason, the recovered materials ran be returned to a ISF column for further processing. The objective of this work has been to develop such a method to recover uranium and plutonium from such off-standard waste streams in a form whereby the uranium send plutonium can be returned to the process line and subsequently purified and separated.
Date: December 31, 1949
Creator: Holm, C.H. & Matheson, A.R.
Partner: UNT Libraries Government Documents Department

Quarterly report, January 1951--March 1951, Chemical Research Section

Description: The current Relox flowsheet proposes precipitation of plutonium peroxide from IIBP solution concentrated by evaporation to 10 g Pu/1 and ca. 5.5 M HNO{sub 3}. Such a solution might have an Al{sup +++} concentration as high as 0.02 M with stainless steel corrosion product concentrations of the order of magnitude of those found in AT solution diluted to 10 g Pu/l. Methods for the precipitation of plutonium peroxide from this type of solution, either with or without partial neutralization of the nitric acid have been described (HW-20053, pp 4-5). Recent work has been devoted to an investigation of the extent to which aluminum, chromium, iron, and contaminating elements are separated from plutonium by peroxide precipitation.
Date: April 16, 1951
Creator: Hill, O.F. & Leitz, F.J.
Partner: UNT Libraries Government Documents Department

Chemical development Separations Technology Unit. Progress report

Description: The Redox Plant operated at a 76.7% time efficiency (IAF basis) and averaged 3.16 tons of uranium per operating day during the month. During the period from July 4 through July 13, 38,000 gallons of 72% ANN from Tygon-lined storage tank SS-112 were used in aqueous salt solution make-ups with some emulsion difficulty and fission-product carry-over resulting. New ANN, from stainless-steel tanks, was used for the balance of the month. An extensive (thermally) hot 60% HNO{sub 3} cleanout was given to the IA, IB, 2D, 3D, 2A, and 3A columns and associated salt solution head tanks to prepare the solvent-extraction battery for operation using 90-day `cooled` uranium. Continuous cross-over oxidation to improve 2A Column waste losses, and employment of KOH (vice NaOH) in 2DS, ICU, and 2EU butt additions to minimize Na in 3EU, were begun concurrently on July 20. Aged (90-day) uranium in head-end treated feed batches, was started to the IA Column on July 21, with early data indicating adequate two-cycle decontamination for both uranium and plutonium.
Date: July 31, 1952
Creator: Woodfield, F.W.
Partner: UNT Libraries Government Documents Department

Completion report, Purex and Redox Phase 2 expansion: Jobs 1063 and 1063R. Volume 1

Description: Vitro Corporation of America entered into a contract with the US Atomic Energy Commission on July 2, 1952 to furnish architect-engineering services in connection with the design and construction of a new chemical plant facility located in the 200 Area of the Hanford Works, Richland, Washington. This contract provided for engineering of facilities utilizing the Purex process to separate and decontaminate uranium and plutonium contained in slugs irradiated in Hanford reactors. Later, Vitro was requested to provide architect-engineering services for an expansion of the previously constructed Redox separation facility. This work, designated as ``Redox Phase II Expansion,`` was authorized by Modification No. 1 to the above contract and was executed April 17, 1953. This completion report has been prepared at the request of the AEC and is intended to provide a convenient source of information concerning the administrative history and engineering features of the Purex plant and the Redox Phase II Expansion.
Date: May 1, 1955
Partner: UNT Libraries Government Documents Department

Addendum to HW-34882: Technical appraisal of Redox ruthenium problems and their resolution

Description: In the light of Redox Plant performance since the start-up on 2-3-55, coupled with a review of the technological factors involved in the current flowsheet, a departure from the process program outlined in HW-34882 is herewith presented as an addendum to that document which will also serve to detail the corresponding items in the latest Redox Test Program, HW-35069. The purposes of this document are to: (1) Discuss the need for modifications of the program given in HW-34882, and (2) Present the details of the proposed revisions.
Date: February 24, 1955
Creator: Harmon, M. K.
Partner: UNT Libraries Government Documents Department

E-metal dissolvers, Redox

Description: In December 1957, the proposal for Project CG-772, ``E-Metal Dissolvers -- Redox`` was returned for reconsideration in order that the units might be designed to accommodate higher enrichment fuels, if practical. Alternate design approaches have been under consideration since that time. It is the purpose of this document to summarize the parameters involved and to present the recommendation developed from the joint thinking of Hanford Laboratories, Research and Engineering, Facilities Engineering, and Redox Operation.
Date: February 19, 1958
Creator: Tomlinson, R. E.
Partner: UNT Libraries Government Documents Department

Definitive process design, Redox multi-purpose dissolver installation

Description: This document provides the required definitive scope design for dissolver equipment capable of nuclear safe processing by geometry of E-Metal and certain other fuels enriched to a maximum of one per cent U-235 equivalent. Using only a single dissolver installation of this design, it will be possible to process the current E-Metal monthly commitment in less than two weeks (five-day week). The proposed dissolver system is to incorporate design flexibility required to permit conversion to Zirflex processing of NPR fuels.
Date: May 6, 1959
Creator: Gustafson, L. D.
Partner: UNT Libraries Government Documents Department

Redox decontamination performance

Description: Since start-up of the Redox Plant, different types of decontamination difficulties have been experienced and corrective measures taken. Current decontamination performance is superior to that ever experienced before. However, with the apparent need for the for elimination of the permanganate Head-End process for the IAF oxidation, several modifications to the plant flowsheet and equipment have been planned in order to obtain satisfactory overall decontamination without permanganate Head-End. The objectives of the memorandum are: to summarize generally and briefly the decontamination experience of the Redox process operating on IAF oxidized by sodium dichromate; to indicate the decontamination which probably can be obtained with the new Phase 2 equipment and its improved performance; and to re-evaluate the timing and feasibility of the current approaches for solving the long-range Redox decontamination problems arising as a result of oxidation of IAF by sodium dichromate (vice potassium permanganate).
Date: December 23, 1954
Creator: Irish, E. R.
Partner: UNT Libraries Government Documents Department

Revised definitive process design, E-metal dissolver equipment, Redox Facility

Description: The purpose of this report is to present the revised process design to be used as the basis for the detail design of Redox dissolvers each of which shall meet the following: Process irradiated natural uranium slugs (standard Hanford or I&E type) at 43% of Phase II Redox production rates; process irradiated enriched uranium up to .94% U{sup 235} isotopic content in slugs (standard Hanford or I&E type) at rates up to 43% of Phase II capacity; and process irradiated fuel elements of cluster design from new reactors with cladding material of aluminum or zirconium, enrichments to .94% U{sup 235} and dimensions of ten feet long and 10 inches square. This report is also to form the basis for slug distribution tests to be performed by HLO concurrent with the final design effort.
Date: March 31, 1958
Creator: Graf, W. A.
Partner: UNT Libraries Government Documents Department

Tank 241-S-111: Tank characterization plan

Description: This document is a plan which serves as the contractual agreement between the Characterization Program, Sampling Operations, ORNL, and PNL tank vapor program. Scope of this plan is to provide guidance for sampling and analysis of vapor samples from tank 241-S-111 (this tank is on the organic and flammable gas watch list). This tank received Redox plant waste, among other wastes.
Date: March 7, 1995
Creator: Homi, C. S.
Partner: UNT Libraries Government Documents Department

Small-Scale High Temperature Melter-1 (SSHTM-1) Data Package. Appendix B

Description: This appendix provides the data for Alternate HTM Flowsheet 2 (Glycolic Acid) melter feed preparation activities in both the laboratory- and small-scale testing. The first section provides an outline of this appendix. The melter feed preparation data are presented in the next two main sections, laboratory melter feed preparation data and small-scale melter feed preparation data. Section 3.0 provides the laboratory data which is discussed in the main body of the Small-Scale High Temperature-1 (SSHTM-1) Data Package, milestone C95-02.02Y. Section 3.1 gives the flowsheet in outline form as used in the laboratory-scale tests. This section also includes the ``Laboratory Melter Feed Preparation Activity Log`` which gives A chronological account of the test in terms of time, temperature, slurry pH, and specific observations about slurry appearance, acid addition rates, and samples taken. The ``Laboratory Melter Feed Preparation Activity Log`` provides a road map to the reader by which all the activity and data from the laboratory can be easily accessed. A summary of analytical data is presented next, section 3.2, which covers starting materials and progresses to the analysis of the melter feed. The next section, 3.3, characterizes the off-gas generation that occurs during the slurry processing. The following section, 3.4, provides the rheology data gathered including gram waste oxide loading information for the various slurries tested. The final section, 3.5, includes data from standard crucible redox testing. Section 4.0 provides the small-scale data in parallel form to section 3.0. Section 5.0 concludes with the references for this appendix.
Date: March 1, 1996
Partner: UNT Libraries Government Documents Department

Evaluation of packed-bed and fluidized-bed cell technology for the destruction and removal of contaminants in alkaline waste solutions. Final report

Description: Disposing of the large quantity of nuclear waste that has been produced within the DOE complex is an area of active research and development. Electrochemical processes have been reported for the treatment of alkaline wastes including the destruction of nitrate and nitrite and the removal of metals such as Tc and Ru. Electrolytic recovery of metals from dilute solution has been reported using conventional porous electrodes such as felt electrode and reticulated electrode, but use of such electrodes is limited. The pores of such electrodes become blocked as a consequence of metal deposition. If an attempt is made to regenerate these electrodes by dissolution of the deposited metals, oxygen evolution on the matrix competes with dissolution of metals deposited within the pores. On the other hand, the use of three dimensional packed-bed and fluidized-bed electrodes having large surface area per unit volume would offer an improvement on felt or reticulated system because of the greater ease of regeneration.
Date: December 31, 1995
Creator: Hobbs, D.T.; Bockris, J.O.M. & Kim, Jinseong
Partner: UNT Libraries Government Documents Department

Characterization and Leach Testing for REDOX Sludge and S-Saltcake Actual Waste Sample Composites

Description: This report describes processing and analysis results of boehmite waste type (Group 5) and insoluble high Cr waste type (Group 6). The sample selection, compositing, subdivision, physical and chemical characterization are described. Extensive batch leach testing was conducted to define kinetics and leach factors of selected analytes as functions of NaOH concentration and temperature. Testing supports issue M-12 resolution for the Waste Treatment Plant.
Date: July 10, 2008
Creator: Fiskum, Sandra K.; Buck, Edgar C.; Daniel, Richard C.; Draper, Kathryn E.; Edwards, Matthew K.; Hubler, Timothy L. et al.
Partner: UNT Libraries Government Documents Department