US Patent 8182696 Multicolumn sequential separation process

A process is disclosed for separating biomolecules from an aqueous solution containing the biomolectules and impurities, having different affinities and/or interactions with a solid support. The solution is passed over a fixed bed of chromatographic resin containing at least three zones, with flow of liquid being arranged between adjacent zones and between a last and first zone. Each of several sequences includes at least an adsorption stage, a rinsing stage, or a desorption stage, with each subsequent sequence being carried out by a downstream displacement of fronts in the zones by approximately the same increment before the periodical displacement of the introduction and withdrawal points.