An anion-exchange chromatographic study on chlorine isotope effect accompanying hydration
Abstract
The single-stage separation factor of the chlorine isotopes (^{35}Cl and 37Cl) was determined to be 1.00034 by 4.5 meter-long anion exchange chromatography operated in the reverse breakthrough manner at 25°C. The value was in good agreement with those obtained in our previous works. It was confirmed that the lighter isotope (^{35}Cl) was preferentially fractionated into the resin phase whereas the heavier one (37Cl) into the aqueous phase. This observation, however, contradicted the experimental result on the Cl isotope fractionation during NaCl precipitation and the recent theoretical result on Cl isotope fractionation: The 37Cl isotope selectively enriched into the solid phase rather than aqueous phase. The discrepancy was discussed on the basis of the theory of isotope distribution between two phases. It was suggested that the chromatographic results were contributed by the isotope effect accompanying hydration more than by the isotope effect due to the phase change, whereas the reverse was the case with the result in the NaCl precipitation study.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2006
- Bibcode:
- 2006AGUFM.V14C..01M
- Keywords:
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- 1021 Composition of the oceanic crust;
- 1031 Subduction zone processes (3060;
- 3613;
- 8170;
- 8413);
- 1041 Stable isotope geochemistry (0454;
- 4870);
- 1051 Sedimentary geochemistry