Determination of Uranium in Urine using EIChrom Resins

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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 protocol Part 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
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Results using different methods
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Results- Different methods (real urine)
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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
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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?