Elution and Mounting Techniques for Americium using Eichrom TRU Resin

Mitch AbbateRadiochemistry Technical DirectorSevern Trent Services St. Louis

May 2, 2002

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Current Method/Standard Eichrom Method

1 Elute with 2 ml of 9 N HCl, then 15 ml of 4 N HCl.

2 Transfer to beaker with DI water.

3 Cook to near dryness.

4 Add one ml concentrated HCl, heat and transfer to 50 ml centrifuge tube with DI

water, dilute to 15 ml.

5 Add Hydrogen Peroxide to oxidize U.

6 Add Neodymium carrier and one ml of concentrated HF, swirl. Let sit 30

minutes.

7 Filter through 0.1 µm filter, rinse with water and ethanol.

8 Dry and mount.

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Increase Productivity, Eliminate Chance for Contamination.

1 What steps can be changed or eliminated to speed up the process?

2 What steps can be changed to eliminate possible contamination?

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Discovery

1 Is it necessary to use 9 N HCl to elute the Americium from the column?

2 Is the presence of the extractant from the resin interfering with the precipitation being formed?

3 Do alphas have trouble penetrating the organic layer, reducing alpha recovery?

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Checking out the 9 N HCl step.

1 Adsorption curve for Americium on TRU Resin out of HCl.

2 Talk to Eichrom.

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Elimination of the Extractant Interference.

Is the organic soluble in alcohol?

1 Ethanol.

2 Methanol.

3 Isopropyl.

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Increase amount of Hydrofluoric Acid1 As seen previously, extra HF can improve

recoveries.

2 Logically the more Fluoride in the solution, the better chance to form Neodymium Fluoride.

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Extra Neodymium carrier.

1 Is more better?

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New Process1 Use 18 ml of 4 N HCl to elute Americium.

2 Add Hydrogen Peroxide and Neodymium carrier.

3 Add 7 ml of concentrated HF.

4 Let sit 20 minutes.

5 Add two drops Neodymium carrier.

6 Let sit 10 minutes.

7 Filter through 0.1 µm filter.

8 Rinse with 5 ml DI water, rinse with 5 ml Isopropyl

alcohol.

9 Dry and mount.

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LCS sample Calcium Phosphate ppt.

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Ground Water sample Calcium Phosphate ppt.

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Conclusion

1 It is possible to eliminate the 9 N HCl elution step for

Americium.

2 It is possible to recover Americium out of elution solution without the cook down step.