Center-cut separation of intermediately adsorbing target component by 8-zone simulated moving bed chromatography with internal recycle.
An 8-zone simulated moving bed chromatography with internal recycle (8ZSMB-IR) has been designed for center-cut separation, that is, for isolating an intermediately adsorbed component out of a multicomponent mixture. The system consists of two integrated subunits and operates in a fully continuous manner. In the first subunit the feed mixture is split into two fractions containing either a single component or a binary mixture. The binary mixture is recycled through the internal raffinate or extract port into the second subunit, where the target product is isolated. Additionally, the solvent is also recycled internally. For a case study, the separation of a ternary mixture of cycloketones as a model system under weakly non-linear isotherm conditions has been investigated. A few novel configurations of the 8ZSMB-IR unit including the arrangement of the internal recycle of extract, raffinate and solvent streams between two subunits have been examined with respect to various performance indicators for the process realization. The unit performed best with the developed configuration when the internal raffinate stream was recycled and the solvent recycling loop was closed between the last and the first zone of the first subunit. That configuration has further been analyzed experimentally and numerically. On the basis of the results a strategy for determining reliable operating conditions for the 8ZSMB-IR process has been developed. The procedure exploited a model of the process dynamics, which was implemented to refine the isotherm coefficients and to quantify the mixing effect of the liquid stream inside the recycling loops. The upgraded model with the adjusted parameters has been validated based on experimental data and successfully applied for optimizing the operating conditions of the separation.
Max Planck Institute for Dynamics of Complex Technical Systems, 39106 Magdeburg, Germany.
Dawid
D
Kiwala
Max Planck Institute for Dynamics of Complex Technical Systems, 39106 Magdeburg, Germany.
Jadwiga
J
Mendrella
Department of Chemical and Process Engineering, Faculty of Chemistry, Rzeszow University of Technology, 35959 Rzeszow, Poland.
Dorota
D
Antos
Max Planck Institute for Dynamics of Complex Technical Systems, 39106 Magdeburg, Germany; Institute of Process Engineering, Faculty of Process and Systems Engineering, Otto von Guericke University Magdeburg, 39106 Magdeburg, Germany. Electronic address: seidel-morgenstern@mpi-magdeburg.mpg.de.
Andreas
A
Seidel-Morgenstern
D000327:Adsorption; D002845:Chromatography / Q000379:methods*; D007659:Ketones / Q000302:isolation & purification; D008962:Models, Theoretical; D012997:Solvents / Q000737:chemistry
D007659:Ketones; D012997:Solvents
Center-cut separation; Cycloketones; Dead volume; Simulated moving bed chromatography; Ternary mixture