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Page 16747
A European Perspective on theUse of Eichrom Resins
Dr Jon Martin
BNFL
Page 26747
Hunterston A
BerkeleyOldbury
Dungeness A
Littlebrook
Chapelcross
Calder Hall
Wylfa
Sizewell ABradwell
Trawsfynydd
Hinkley Point A
Maentwrog
Sellafield
Risley HQ
BNFL UK Sites
Page 36747
An Overview (1992-1998)
Background
Initial use in emergency response planning.
Application to simple matrices.
A difficult problem - resolved with Ln.Resin.
Application to environmental matrices.
Accreditation for plant-support methods.
The broader picture.
Page 46747
Page 56747
Page 66747
Page 76747
Environment
MagnoxAGR
Liquid & GaseousEffluent
WasteCharacterisationLab.
DecommissioningLab.
Low Level Waste
IntermediateLevel Waste
CentralRadiochemical
Laboratory
CRL Lab Overview
Page 86747
Extraction Chromatography - Application to Emergency Methods
“The aftermath of an accident is not a time to begin the development of novel procedures”. N. Green, NRPB
• EEC Intervention Levels:
Material Limiting Activity ConcentrationSr-89/Sr-90 Pu-239, Am-
241, Cm-242/4Others with t1/2 >10
days(excl. H-3 / C-14
Dairy produce &liquid foods (Bq/kg)
125 20 1000
Solid & LiquidFoods (Bq/kg)
750 80 1250
Page 96747
Sequential Emergency Procedure
Add radionuclidespikes
Microwave digest
Anion exchangecolumn
Electrodeposit orcoppt Pu
Sr , Am, Cm notretained
Sr .Resin
Sr -89/90determination
Am, Cm fraction toTRU.Resin
Coppt Am / Cmsource
Page 106747
Rapid Sr-89 / 90 Procedure
Elute from Sr .Resin in 8ml water
Cerenkov count (15min)
Sr -85 yield determination
Add Ultima Gold XR
Calculation of Sr -89 & Sr -90 - Correction for Y-90
Liquid scint . count
Page 116747
Limitations Sample size.
Large excess of Am-241
over Am-243 yield tracer.
Uranium breakthrough in
Pu spectrum.
Batch size dominated by
microwave digestion.
Sampling uncertainty.
Merits <24 hour turnaround,
incl. Screening of 80
samples & analysis of 6.
Addresses required
limits of detection and
accuracy.
Introduced the benefits
of extraction
chromatography…
Page 126747
Summary of routinemethodology…1
Analysis Classical separation Extractionchromatography
Comments
Tritium Distillation Tritium.Resin investigated butclean-up not sufficient for Magnoxeffluent.
C-14 Wet / dry oxidation
S-35 Wet oxidation andchemical isolation and /or cation exchange
C1-36 Chemical isolation
Ca-45 Chemical isolation Sr.Resin + classicalchemistry
RE.Resin investigatedbut little Mn-54 clean-up
Mn-54 Chemical isolation
Fe-55 Solvent extraction
Ni-63 Ni.Resin
Page 136747
Summary of routinemethodology…2
Analysis Classicalseparation
Extractionchromatography
Comments
Sr-90 / Sr-89
Sr.Resin Excepting large volume milksamples
Tc-99 TEVA.Resin Low requirement
I-129 Solvent extraction ABEC.Resin Extraction chromatography notnormally necessary
Pm-147Sm-151
Ln.Resin
Pb-210 Sr.Resin
Po-210 Distillation or directauto deposition
Sr.Resin
Ra-226
Uranium /Thorium
U/TEVA.Resin /TEVA Resin
Transuranics TEVA / TRU.Resins
Page 146747
Pm-147 High abundance in fresh fission
product mixtures.
Sm-151Increasing importance in decayed
fission product mixtures.
Pm-147 / Sm-151Analysis...Why?
Pure soft -active radionuclides. Radiotoxicity comparable to that of carbon-14.
No suitable isotopic yield tracer.No naturally occuring isotope.
No suitable isotopic yield tracer.Gravimetric yield determination
possible.
What yield tracer?
Page 156747
Assessment of ‘Low Abundance’ Isotopes' compliance with de minimis Criteria for Disposal
Radionuclide Maximum TheorecticalActivity per Consignment
de minimis
Se-79 0.0075 13Y-91 10300 13Zr-93 0.0047 13Nb-93m 0.029 13Tc-99 0.37 13Pd-107 0.002 13Sn-126 0.28 13I-129 0.00069 0.05Cs-135 0.019 13Sm-151 6.3 13
Page 166747
Ce Pr Nd Pm Sm Eu Gd Tb HoDy TmEr Yb Lu
Ho-166m [1200y, ]
Eu-154 [8.59y, 580 keV]........1.9
Eu-155 [4.85y, 160 keV]........2.6
Sm-151 [88.7y, 76 keV].....................0.31
Pm-147 [2.6y, 225 keV].............................79
Pr-144 [285d, 2.996 keV]
Ce-144 [285d, 318 keV]..........................................................23
Ab
un
dan
ce r
el. t
o C
s-13
7 (%
)@
5G
Wd
/T, 4
yea
rs d
ecay
ed
Pm-147 / Sm-151Analysis...Interferences
Page 176747
Ce Pr Nd Pm Sm Eu Gd Tb HoDy TmEr Yb Lu
Natural Samarium...natural
Natural Neodymium...natural
Gd-148, [3.27 MeV]
Pm-147 Analysis...Yield tracers
Page 186747
Ln.Resin - not to be confused with RE.Resin (of course!)
HDEPH: bis(2-ethylhexyl) phosphoric acid supported on Amberchrom CG-71 at a 40%w/w loading.
Original work by Horwitz & Bloomquist, J. Inorg. Nucl. Chem. 17, 425 (1975).
Promethium-147 by Eichrom’s Ln.Resin
Page 196747
Am
Eu
0 10 20 30 40 50 60 700.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
Nor
mal
ised
cou
nt r
ate
(Arb
)
Volume (cm3)
Am
Pm
Gd
0.15 M nitric acid 0.25 M nitric acid 0.4 M nitric acid
Pm-147 / Sm-151Analysis...Gd-148 yield tracer
Page 206747
0 50 100 150 200 250 3000.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
Nor
mal
ised
cou
nt r
ate
/ Sm
con
cent
rati
on (
Arb
)
Volume (cm3)
Pm-147 / Sm-151Analysis...Natural Sm yield tracer
Page 216747
Summary of Pm-147 / Sm – 151 Results
Sampledescription
Pm-147 Result Sm-151 Result Ratio
FMDT liquid effluentannual bulk (15/06/97)
698 + 49mean of 4 results
9.28 + 2.83 75 + 24
AETP sludgedissolution liquor – A
2.40 + 0.20 1.92 + 0.22 1.25 + 0.18
AETP sludgedissolution liquor – B
1.35 + 0.15 0.949 + 0.099 1.42 + 0.22
ILW resin sample(Lewatit DN)
18.3 + 1.4 13.0 + 1.0 1.41 + 0.15
LLW QC spikedsolution
(-2.8 + 10.8)%
Page 226747
Benefits
Approximate 60% cost reduction per analysis through time savings and larger batches.
Fully validated, accredited methods with comprehensive uncertainty budgets.
Methods proven at national and international intercomparison exercises.
Page 236747
Environmental / Bioassay Matrices - Overcoming the Interferences
Sr-90 in fish, urine, faecal ash.3g Sr.Resin in column.
Pu / Am in soils. Anion exchange pre-clean-up.
Preliminary work on pre-concentration of transuranics on Diphonix, followed by Fenton’s Reagent destruction of organics - see work by Bill Burnett, FSU.
Page 246747
Application of Eichrom technology to other BNFL processes
Support to reprocessing: product quality and accountancy.
Tc-99 analysis - TEVA - various matrices.
Environmental monitoring programmes.
Application of Eichrom technology in EuropeMature processes which are broadly used in a wide range of applications.PROCORAD - laboratories from >20 countries. Many used Eichrom extractants.