1. The Determination of 226 Ra in Water Samples Anil H. Thakkar Eichrom Technologies, Inc. eichrom TECHNOLOGIES INC

2. Objective To design a procedure for radium in water samples using Eichrom’s cation exchange resin and Ln Resin. eichrom TECHNOLOGIES INC

3. Current Procedure Used Barium sulfate precipitation Conversion to BaCO 3 - tedious and time consuming eichrom TECHNOLOGIES INC

4. eichrom TECHNOLOGIES INC Sample + Ba carrier + Ba-133 + Conc.H 2 SO 4_ + Heat BaSO 4 Precipitate allowed to settle for several hours or overnight Precipitate collected and converted to BaCO 3 Current Procedure Used

5. New Approach Water samples Cation exchange resin column Eichrom Ln Resin column eichrom TECHNOLOGIES INC

6. Preparation of Water Samples 0.5 L / 1.0 L water samples, acidified to pH 2 Add 133 Ba as a tracer eichrom TECHNOLOGIES INC

7. Eichrom Cation Exchange Column Load solution: 0.5 L/ 1.0 L of sample Rinse with 50 mL of 0.1M HNO 3 Strip Ra and Ba with 50 mL of 8M HNO 3 eichrom TECHNOLOGIES INC

8. Preparation of Load Solution for Ln Resin Column Evaporate eluent from cation exchange column to dryness Dissolve residue in 10 ml of 0.095M HNO 3 acid Load on Eichrom Ln Resin column eichrom TECHNOLOGIES INC

9. Ln Resin Column Separation (1) Load: 10 mL of mL 0.095M HNO 3, (3) Strip: 10 mL of 0.35M HNO 3 Collect 1) and (2) for Ba & 226 Ra collect (3) for 228 Ac (2) Rinse: 15 mL of 0.095M HNO 3 eichrom TECHNOLOGIES INC

10. 226 Ra Via Alpha Spectrometry Evaporate 226 Ra/ 133 Ba fraction to 10 mL volume Add 3 mL of 40% sodium sulfate, 4 drops of 1:1 acetic acid. Swirl Add 0.2 mL of seeding suspension. Mix Place tubes in cold water bath for 30 minutes Filter on 0.1 micron filters, count via alpha spectrometry eichrom TECHNOLOGIES INC

11. 133 Ba Via Gamma Counter Count 133 Ba tracer yield via gamma spectrometry eichrom TECHNOLOGIES INC

12. 228 Ac Via Gas-Flow Proportional Counter Add 50 micrograms of cerium carrier Add 1.0 mL of HF Filter on 0.1 micron filters Measure for beta radiation eichrom TECHNOLOGIES INC

13. 226 Ra % Recoveries-0.5L DI Water eichrom TECHNOLOGIES INC

14. 226 Ra Alpha Spectrum eichrom TECHNOLOGIES INC

15. 133 Ba Gamma Spectrum TECHNOLOGIES INC eichrom

16. 226 Ra, 224 Ra, and Daughters eichrom TECHNOLOGIES INC 226 Ra 222 Rn 224 Ra 218 Po 220 Rn

17. 226 Ra % Recoveries in Tap water eichrom TECHNOLOGIES INC

18. 226 Ra in EPA Sample Sept.18, 1998 eichrom TECHNOLOGIES INC

19. Summary Cation exchange resin option: –provides a good replacement for the time consuming BaSO 4 precipitation steps –it eliminates inconsistent metathesis steps –reduces usage of chemicals/reagents –provides consistency and saves time Acceptable 226 Ra recoveries eichrom TECHNOLOGIES INC