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Hydroxo Compounds in 0.5 - 14 M Naoh Solutions

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Hydroxo Compounds in 0.5 - 14 M Naoh Solutions WHC-EP-0987 Determination of the Solubility of Np(lV)-(VI), Pu(lll)-(Vl), Am(lll)-VI) and Tc(lV), (V) Hydroxo Compounds in 0.5 - 14 M NaOH Solutions 'V. F. Peretrukhin IS. V. Kryutchkov 'V. 1. Silin /I. G. Tananaev 1,nstitute of Physical Chemistry IRussian Academy of Sciences IDate Published September 1996 Prepared for the U.S. Department of IEnergy Assistant Secretary for Environmental Management Westinghouse P.O. B~~ 1970 0Hanford Company Richland. Washington Ib4anagement and Operations Contractw fa the 1J.S. Department of Energy under Contract DE-ACO8-8713L10930 Approved for public release; dlistribution is unlimited RELEASE AUTHOR12IATION Dalcuinent Number: WHC-EP-0897, Rev. 0 ~-- Determination of the So'ubility of Np(1V)-(VI), Dalcuinent Title: Pu(111)-(VI), Am(II1)-(VI), and Tc(IV), (V) Hydroxo Compounds in 0.5 to 14 11 NaOH Solutions Release Date: 9/24/96 This document was reviewed following the procedures described in WHC-CM-3-4 and is: APPROVED FOR PUBLIC RELEASE ---- ~-- WHC Information Release Administration Specialist: c A-6001-400 (07/94) UEF256 LEG4LDLMXAlMER - Msreport wgprepared ea an eccwnt of work opomred Iby an awncy of tho United States Governant. Neithsr the IJnIted Stata Gowrmmnt nor any agency thereof, nor any (of their arplovaa Mrany of thdr Controcton. subcontractors or thoir mplopes, makes any warranty. sxpreap or implied, ctr asa~mwany lege4 lisbility or rsqonibility for ths aocuracy, conplatenass. or any thud paws USI) or the rewlts of such us0 of any information, apperstus. product. or process dipdosed. or represents tbt its uw would not infringe privatdy ow4righu. Rafarsnca herein to any specific conmsrcid product. p~octm.or earvice by trade ram. ti'daurrk. marufactursr, or 0tharwi.a. does not necessarily coruti~eor inply iu andoreansnt. rscarrmsndation. or fmmrirq by tho Uritad States Goverrment or any a~sncy tlwrwf or its contractors or subcontractors. The n'ews and O~~NOMof arthorn swrsssed harein do not necessarily state or reflect those of tho United States Govermnt or any awncy thoreof. - Ttis report has been reprducd from the best avaiI.de copy. Availeble in paper cwy and microfiche. Availeble to fhs U.S. Depamnsnt of Energy aid its contracton frm US. Depemnsnt of EMrW Offce of Scisndfic and Technical Informetion (OSTI) P.O. Box 62 O,& &dp. TN 37831 I8151 5758401 A~lSilaMto tho public frmths U.S. Department of Commerce Ntdond Technical Information Service INTIS] Port Royd Roed Spnnofidd. VA 22161 CI031487-4650 hndn dw IJ-d SWof - DlljCLMl .CHP (8-951 RELEASE AUTHORIZATION Document Number: WHC-EP-0897, Rev. 0 Determination of the Solubility of Np(1V)-(VI), Document Title: Pu(111)-(VI), Am(II1)-(VI), and Tc(IV), (V) Hydroxo M -- Compounds in 0.5 to 14 NaOH Solutions Release Dtate: 9/24/96 This document was reviewed following the procedures described in WHC-CM-3-4 and is: APPROVED FOR PUBLIC RELEASE WHC information Release Administration Specialist: September 24, 1996 A-6001-400 (07194) YEf256 INFORMATION RELEASE REQUEST - (Long Form) IGFIAY SHADED AREAS NOT TO BE FILLED IN BY INITIATORI 7-2 / I COMPLETE THIS SECnON FOR ALL DOCUMENTS A Information Category B Document ID Number lincluda rev, MI stc I Speech or Presentation Ix] Full Paper 0 Journal Anide WHC-EP-0897 0Abstract 0Softwiire 0Visual Aid I7 0th.' --~I D. Document Tnis Determination of the Solubility of Np(1V)-(VI), and Tc(IV),(V) Hydroxo Compounds in 0.5 to 14 M NaOH Solutions Development ---- I F. New or novel lpatentobisl rubioct matter? G. lnformatbii rweiwd from othsrr in confidence. such as proprietary data, [HI No a'Ys' If 'Yes". has discloawe been submitted by WHC? and/or invention.? NO or yss It sa", Disclowre NOM: [HI No or Yes If 'Yes". contact WHC General Counsel. +I Copyrights? [HI No or Yes If "Yes', attach permission. I. Trademark.? [PI No or Yes If "Yes., identify in document. 2. COMPLETE THIS SECTION FOR ALL DOCUMENTSREOUIRING SUBMISSIONTO OSTl A Unclassified Category UC - 0601 8. Budpet & Feponinp Code B&R - EW4030 3. COMPLETE THIS SEC77ON ONLY FOR A JOURNAL SUBMISSION Pi Title of Journal -______- -_______- 4. COMPLETE THIS SECTION ONLY FOR A SPEECH OR mESENTATION Pi Title for Conference or Meeting B. Gmup or S,>ciety Sponsoring ___- ~ 1 c. Dateis! of conference o cnyistata E in or Meeting Will materiati be published prmcosdmgs? 0 No or Yes 1 Will materiiii be handed out? Reply Separator -- Subject: Re[Z]: Clearance fOt WHC-EP-0897 Author: James P HIanson at -DOE20 Date: 9/23/96 12:36 PM Cal, Please proceed with clearance for this document per this cc:mail Jim Hanscin _____-~ Reply Separator ___ Subject: Re: Clearance for WHC-EP-0897 Author: Calvin H Delegard at -HANFORD03C Date: 9/17/96 6:51 AM Thanks for your attention to this, Cal cal, It is on its way... snet to Kara Broz tonight ...Plant Mail. Sorry, I have beer, swa.mped with the ten-year-plan and personnel issues, JPH -~ Reply Separator ___ Subject: Clearance for WHC-EP-0897 Author: Calvin H Delegard at -HANFORD03C Date: 9/16/96 3:26 PM Jim, A cc8uple weeks ago, I sent you a draft cop:{ of the document WHC-EP-C'E97 for your review and clearance. The document concerns the solubility of the actinides and technetium compounds in alkaline solution -- the work was done by the Institute of Physical Chemistry in Russia. I want to issue the document before the contractor transition. Please advise rile of the status of your clearance. I'd be glad to answer any questions. Thanks, Cal Message Contents ____________________________________ This message is to document my approval for clearance of WHC-EP-0897 on Actinides and Technetium in Alkaline Media by V. F. Peretrukin et al. I understand the original approval sheet has been lost. J. n. Jewett, Manager Process Chemistry and Statistics , , 111 WHC-EP-0897 DETERMINATION OF THE S0:LUBILITY OF Np(W - (Vn, PuO- 0,Am(W - (VU,AND Tc(W, (V) HLYDROXO COMPOUNDS IN 0.5 - 14 Fvl NaOH SOLUTIONS ABSTRACT The solubilities, of Am(III), Np(IV), PuQV), TcQV), Np(V), Pu(V), Am(V), and Tc(V) hydroxo compounds were studied in 0.5 to 14 M NaOH solutions at 25+2 "C. The effects of fluoride, phosphate, carbonate, oxalate, and some other organic complexing agents on the solubilities of Np(IV), Pu(IV), and Tc(IV) hydroxides were investigated at 1.0 and 4.0 M NaOH. Some predictions were made on the dissolved (IV) and (V) species present in alkali solutioins. This page intentionally left blank. WHC-EP-0897 EXECUTIVE SuMMpiRY The solubilities of Am(III), Np(IV), Pu(IV), Tc(IV), Np(V), Pu(V), Am(V), and Tc(V) hydroxlo compounds were studied in 0.5 to 14 M NaOH solutions at 25k2 "C. The effects of fluoride, phosphate, carbonate, oxalate, and some othl:r organic complexing agents on the solubilities of Np(lV), Pu(IV), and Tc(IV) hydroxides w<xeinvestigated at 1.0 and 4.0 M NaOH. Predictions were made on the dissolved (IV) and (V) species present in alkali solutions. The sdlubilities, of NpO,mH,O and Pu02.nH20were measured in 0.5 to 14 M NaOH in the presence of 0.1 M N,H, under conditions designed to prlcvent their oxidation by atmospheric oxygen. The solubilities increase with increasing NaOH concentration from about 3 X to 2.1 x IO" M for Np(IV) and from 1.4x 1W8 to 9.8~lod M for Pu(1V). The formation of the anionic species, Np(0H); and Pu(OH);-, in alkaline solution have been calculated from known values of the solubility products of Np(OH), and Pu(OH), and the experimental data. Spectrophotom'etnc measurements to identify the Np(0H); and Pu(0H):- were unsuccessful because of low extinction coefficients. Complex-forming agents at concentrations from 0.05 to 0.5 M in 1 and 4 M NaOH with reductants yielded Np(1V) and Pu(1V) hydroxide solubilities increased 2 to 400-times from those observed in the absence of the agents. The solubilities of Np(V), Pu(V), and Am(V) hydroxo compounds were found to be higher than those of the tetravalent actinide hydroxides and increase from (0.5 to 1.O)X lo4 M to 3.7X 104 as N,aOH concentration increases from 0.5 to 14 M. The composition of the WHC-EP-0897 --- --- neptunium solid phase has been determined by X-ray diffractometry to be NpOzOH.nH20 under 0.5 M NaOH mother solution and Na,Np02(C)H),~nHz0under 5 M NaOH. The formation of N,a,NpO,(OH),.nH,O is assunned at higher alkali concentration. The solution species NpO,OH, [Np02(OH)J2-, and [NpQz(OH)J3- are presumed to exist in 0.5, 5, and 14 M NaOH solutions, respectively. The sollubilities of Pu(IV) hydroxo compounds in NaOH solutions in the presence of hydrazine are 2, to 30-times lower than those obtained by Delegard (1987) in the presence of air and by Kanaker (1993) in evaporation of simulated NaOH waste solutions. The solubiilities of Np(IV) and Pu(IV) achieved in 0.5 to 14 M NaOH in 0.1 M NzH, and the absence of applied external gamma radiation are below the transuranic waste (TRU) threshold of 103 nanocuries per gram solution. The solubility of Np(V)i hydroxide compounds in 1 to 14 M IrTaOH are lower than the TRU threshold whereas the solubilities of the Pu(V) and Am(V) compounds are above the threshold. The solubilitier; of the Tc(IV) and Tc(V) hydrated oxides in 0.02 M N2H4and 1 M NaOH are comparable and about 3 x 10” M.
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