F. Chabaux et al., A NEW RA-BA CHROMATOGRAPHIC-SEPARATION AND ITS APPLICATION TO RA MASS-SPECTROMETRIC MEASUREMENTS IN VOLCANIC-ROCKS, Chemical geology, 114(3-4), 1994, pp. 191-197
We have adapted the recent chromatographic method described by E.P. Ho
rwitz and coworkers for Sr separation, to perform an efficient Ba-Ra s
eparation for measuring Ra isotopes in volcanic rocks by mass spectrom
etry. Extraction chromatography is used with a solution of a crown eth
er (4,4'(5')bis-(tert.-butylcyclohexano)-18-crown-6) in 1-octanol, ads
orbed on an inert substrate as an extractant. The ElChrom Company mark
ets this resin under the name Sr Spec(R). We show that this technique
gives a very efficient Ba-Ra separation which compares favourably with
previous chromatographic methods. The chemical and mass-spectrometric
procedure is described in detail and is applied to Ra measurements in
volcanic rocks.