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Determination of Uranium in Urine using EIChrom Resins. Helen E Carter Loughborough University UK Arthur E Lally OBE RTC Ltd UK Michaela Langer EIChrom Europe France Peter Warwick Loughborough University UK. Evaluation of some methods. Reason for the study - PowerPoint PPT Presentation
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EIChrom User Group Meeting 15/11/99
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Determination of Uranium in Urine using EIChrom Resins
Helen E Carter Loughborough University UK
Arthur E Lally OBE RTC Ltd UK
Michaela Langer EIChrom Europe France
Peter Warwick Loughborough University UK
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Evaluation of some methods
Reason for the study
Inconsistency in results from certain methods
Attribute possible causes
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Problem areas? A satisfactory analytical
result requires
Combination of
Analyst Method Equipment
Instrumentation Laboratory environment Materials and chemicals
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Analyst
Trained limited experience
Limited time to test effectiveness
Manual procedures
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Analytical
Methodology
For this study all were similar
Method A no apparent problems
Method B inconsistencies in results
Method C less of a problem than B
Method D small inconsistencies
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Equipment
Materials EIChrom resin TRU
Batch to batch variation
Storage
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Study protocol Part 1
PhD student - initial work
Familiarisation with techniques using Synthetic urine Genuine urine Co-precipitation Electro deposition
Actual methods
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Study protocolPart 2
Evaluation of data
PhD student finished her work and left
Final tests on hydrolysis to be carried out
Conclusions to be made
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Outline -Method A
Mineralisation with HNO3
Copptn on Ca phosphate Muffle at 900Oc 8 hrs Dissolution HNO3+ Al nitrate Reduction with Fe(II) sulphate TRU resin column Elution with Amm. Oxalate Source preparation Reduction with TiCl3 Micro pptn on CeF3
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Outline –Method B
Mineralise with HNO3/H2O2
Muffle at 500oc 6 hrs Hydrolyse 1.4 M HNO3
Copptn Ca phosphate Ferrous sulphate/ Al2(NO3)3
TRU resin U elution Micro pptn with LaF3
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Outline-Method C
Similar to method B but Muffle 12hrs at 500oC Separation on AGMP1
resin Pu on column U in load + 8M HNO3
wash U fraction on to TRU resin As for method B
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Outline-Method D
Mineralisation and evaporation on hotplate
Hotplate to 500oC 5hrs Dissolution / hydrolysis in
2M HNO3
Co pptn Ca phosphate Dissolution HCl Co pptn Fe phosphate As per method C
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Results - same batch of resin
Method A, Mock Urine Batch TR8B resin CeF3 pptn % recovery 84, 75, 77, 94, 88, 92, 89, 95, 92, 87, 93, 77,
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Results – DifferentBatches of Resin
TR6D 88%
TR6D 91%
TR6D 62%
TR7A 88%
TR7A 55%
TR8C 70%
TR8C 23%*
TR8C 86%
*blocked col.
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Results using different methods
B1 45%
B2 36%
B3 32%
C1 93%
C2 88%
C3 99%
D1 76%
D2 76%
D3 74%
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Results- Different methods (real urine)
A1 78%
A2 71%
A3 76%
B1 28%
B2 30%
B3 28%
C1 67%
C2 Lost in anal.
C3 68%
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Conclusions – to date
Consistency for Method A and analyst satisfactory
Different batches of resin No real evidence of
effect
Different methods A, C and D reasonable B poor
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What is going on? Analyst or method !
Method A always OK Method B always poor
Give the analyst a chance!
What else could be wrong?
HYDROLYSIS ?
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HydrolysisAlways been a problem
Actinides U and Pu love pyrophosphates better than any ion-exchange resin
(yes even EIChrom!) Experiment with
hydrolysis procedures New analyst on job Old analyst in years!!
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Hydrolysis proceduresevaluated using:-
Mock Urine Method B CeF3 micro pptn U-233 spike
Very large prayer mat.
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Method B amendments 1
Samples 1 and 2 Standard 500oC 6hrs Standard 1.4M nitric
hydrolysis and Fe(II) SO4
Samples 3 and 4 As above but 500oC 18hrs
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Method Bamendments 2
Samples 5 and 6
Standard 500oC 6hrs Standard 1.4M nitric but-
with ferrous sulphamate and Fe(II) SO4
Samples 7 and 8
As above but 500oC 18hrs
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Results of hydrolysischanges to Method B
Ferrous sulphate
1 6hrs 81%
2 6hrs 82%
3 15hrs 78%
4 15hrs 79%Ferrous sulphamate
5 6hrs 72%
6 6hrs 70%
7 15hrs 80%
8 15hrs 70%
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Conclusions of hydrolysis changes
No significant differences
Method B appears to give good results
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Overall Conclusions
The resin appears to make no difference with regards to Age Batch Packing
Methods all appear OK at times
What about the operator? Think about method,
operator and equipment combination!
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Summary of all experiments
No effect of resin All methods satisfactory
Human factor Bored staff? Staff in wrong method?
Automation
Who wants an old chemist?