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Updates on New Eichrom Chromatographic Materials For Radium Separation Including

Updates on New Eichrom Chromatographic Materials For Radium Separation Including. MnO 2 DGA Sr2 Natasha Dimova, Bill Burnett - Florida State University E.Philip Horwitz PG Research Foundation. Acknowledgments. FSU Graduate Students Henrieta Dulaiova Ricky Peterson

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Updates on New Eichrom Chromatographic Materials For Radium Separation Including

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  1. Updates on New Eichrom Chromatographic Materials For Radium Separation Including MnO2 DGA Sr2 Natasha Dimova, Bill Burnett - Florida State University E.Philip Horwitz PG Research Foundation

  2. Acknowledgments FSU Graduate Students Henrieta Dulaiova Ricky Peterson PG Research Foundation

  3. MnO2-Resin Simple sample preparation High capacity-Kd=2.4x104 RAD-7 counting system Alpha detector-spectrum of alpha emitters 218Po, 214Po, 216Po RAD-7-MnO2-Resin automated systemfor measurements of 224Ra and 226Ra in water samples

  4. Decay chains of uranium and thorium series Th-232 U-238

  5. The separation of Ra2+ is due to the adsorption of the bi-valent ions on partly negative charge surface of the MnO2 Resin MnO2-Resin: pH dependence Ra 2+ - - Ra 2+ - Ra 2+ - - Ra 2+ - Ra 2+ - - Ra 2+

  6. x x Measurements of 224Ra and 226Ra in water samples: automated system schematic DRYING TUBE 1/4˝ FILTER 224/226Ra on MnO2-RESIN 1/4˝ IN OUT (pump) 1/4˝ 3/16˝ 1/4˝ 1/4˝ RAD-7 1/4˝ TWO-WAY VALVE

  7. Ra-226 (T1/2=1600 y) Flush for 10 min thru cartridge and switch to protocol: ch.A: use after 1st 15 min ( 218Po = 222Rn). ch.(A+C): use after 3 hrs (214Po = 222Rn). use a count time long enough to ensure good counting statistics. Ra-224 (T1/2=3.6 d) The cartridge must be continuously flushed: ch.B: use ~15 min cycle with about 10 recycles. equilibration in the 224Ra–220Rn chain (requires ~ 5 min). use “DRYSTIK” to control moisture. count time long enough to ensure good counting statistics. RAD-7 - MnO2-Resin:recommended protocols

  8. RAD-7 - MnO2-Resin:calibration curve 224/226Ra on MnO2-RESIN TWO-WAY VALVE

  9. Diphonix DGA Resin, Normal Comparison of DGA Resin, Normal and Diphonix: retention

  10. Ra-228 via 2-Column Approach sample in 2M HCL I Diphonix HEDPA – AC sample in 2M HCL II Diphonix Ra2+ hold >30 hrs Ac3+ ingrowth Ra2+ alpha source • LSC • oxidation for discarding organic component; beta counting HEDPA – Ac3+ Nour, S et al. / Applied Radiation & Isotopes 61 (2004) 1173-1178

  11. Diphonix DGA Resin, Normal Comparison of DGA Resin, Normal and Diphonix: elution

  12. 3 + - M ( N O ) E M + 3 N O + 3 E 3 3 3 3 M = L n , A n TN-DGA-extraction chromatographic resin Extractant: N,N,N’,N’-tetra-n-alkyl-3-oxopentanediamide (TN-DGA)

  13. DGA-Conclusions • Strong retention as Diphonix for tri-valent ions: Kd~105 ml/g. • Easier elution from DGA Resin, Normal • direct counting of Ac-228 on beta counter or LSC. • no need of organic (HEDPA) oxidizing step. • eluent dilute acid (0.5M HCl).

  14. Sr2 Resin, Strontium extraction chromatographic resin Extractant: 4,4”(5’)-di-t-butylcyclohexano-18-crown-6 AE 2+ + NO3- +Cr AE (Cr) (NO)3

  15. Summary • RAD-7-MnO2-Resin automated system is a powerful tool for determination of 224Ra and 226Ra in natural waters without chemical separation. • DGA-extraction chromatographic resin has the same high Kd for Actinium as Diphonix with the benefits of easier elution with 0.5M HCl. • Sr2 Strontiumextraction chromatographic resin can be successfully used for Ba/Ra separation.

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