Patent ID: 8216475

Claim:
Process for separating a fraction of a mixture in a discontinuous chromatography device having one or more columns in a loop, a circulating mobile phase shifting the fractions of the mixture to be separated in said loop, injection points for mixture and eluent, fractions collection points, sequencing elements for injection and collection points, the process comprising steps of collecting the fractions, injecting the mixture between two successive collections in the period where the fractions of the mixture leave the column(s) and are sent to the next inlet; wherein the process further comprises the steps of: at a node of the device, monitoring the history of a specific variable of the fractions of the mixture to be separated, detection of a characteristic point of the history, the characteristic point being between two successive fraction collection steps, comparison of the position of the characteristic point with a target position, adjustment of the quantity of the mobile phase modifying the position of the characteristic point in order to make the position of the characteristic point coincide with the target position.