Abstract: A process and an apparatus for separating industrially a large amount of a biopolymer-containing sample by ion-exchange type column chromatography using the gradient elution method, wherein at least two precursor liquids for a mobile phase from liquid baths 3a and 3b are introduced into a mixing device 14 while the flow rate thereof is controlled over a wide range to obtain a mobile phase liquid. The mobile phase liquid thus obtained is introduced into the columns 1a and 1b so that the sample is separated in the columns and the biopolymer is collected in a fraction collector 6. The columns 1a and 1b are alternately regenerated.

Abstract: A separation process by liquid chromatography, which comprises sending a mixture sample in a large amount together with a liquid mobile phase to at least one column, into which a packing having a large particle size has been charged, to preliminarily fractionate the components of the mixture, taking out fractions containing objective components from the eluate from the first column, and recycling said fractions within a loop provided with at least one second column, into which a packing having a large particle size has been charged, to separate precisely the objective components.According to this process, it is possible to separate economically objective components from the sample loaded in a large amount.