Simulated moving bed (SMB) chromatography has become the state of the art technology applied for the complex separation tasks in the pharmaceutical and fine chemical industry. We have developed a feedback control scheme that integrates the on-line optimization and control of SMB units. A significant feature of the developed SMB control concept is that only a minimum of system information has to be provided, i.e., the average packing characteristics of the SMB columns and the linear adsorption isotherm, regardless of the type of isotherm characterizing the mixture to be separated. Therefore a detailed characterization of the columns and the separation system is no longer required. This paper describes the developed on-line optimization based control concept and the experimental verification.