Cation exchange separation of 16 rare earth metals by microscale high-performance liquid chromatography

The separation of rare earth metals has been studied with a micro-column of 0.5 mm i.d.×75 mm length, packed with TSK LS-212 high-performance cation exchange resin 16 rare earth metals were separated within 38 min, using only 304 μl of 0.4M α-hydroxyisobutyric acid solution adjusted to pH 3.1–6.0 with ammonia solution as gradient carrier solution. The gradient elution was successfully performed by applying a new technique developed for microscale liquid chromatography.