Isotope effects of strontium in crown ether chromatography

A fundamental study was made on the chromatographic separation of strontium isotopes with the polymer-supported crown ether resin. Hydrochloric and nitric acids were chosen as the eluent solutions. In each of these systems, the heavier isotopes had been enriched in the front part of the strontium adsorption band. This result means that the heavier isotopes are preferentially fractionated into the solution phase. The largest single-stage separation coefficient (epsilon) for the Sr-84 and Sr-88 pair, 5.5x10(-4), was obtained with hydrochloric acid elution at 35 degreesC. The observed separation coefficients from one-step separation procedures are much larger than those of ion exchange separation systems but smaller than those of crown ether extraction systems. Odd/even or anomalous isotope effects were not observed in the strontium-crown systems studied to date.