We propose a novel technique for the simultaneous isolation and concentration of a target solute from a multicomponent mixture using a continuous rotating annular chromatograph with double-stage partial recycling of the effluent. In this technique, the target solute is first completely isolated from the multicomponent mixture by a partial recycling method in which the effluents of incomplete separation are recycled to the inlet adjacent to that of the raw feed mixture. Next, the isolated solute is re-recycled to the inlet of the region unused for isolation. In order to concentrate the isolated solute, a second eluent removing the solute from the chromatographic packing to the external liquid phase and making the elution band narrower is supplied to the inlet at a larger angle than that of the re-recycled solute. The technique was applied to the simultaneous isolation and concentration of valine from a ternary mixture of amino acids, glutamic acid, valine and leucine. The numerical calculation based on a mass transport model was used to determine the optimum arrangement of the recycling channels and their corresponding nozzles for isolation and concentration of the target solute. The double-stage partial recycling method allowed the target solute, valine, to be completely isolated and concentrated from the initial concentration of 0.1 mol/m(3) to 0.233 mol/m(3).