ABSTRACT The characterization of chromatographic columns is a primary and important step in the determination of the main parameters employed in the modeling of SMB (Simulated Moving Bed) process. In this work the eleven chromatographic columns utilized in a SMB unit of glucose and fructose separation were modeled through a novel modeling approach, the front velocity of convection. In such a modeling approach the experimental volumetric flow rate is employed for the discretization of the volumetric elements moving along the porous column. In the new approach the convection of the liquid phase is the main phenomenon in the transport of molecules along the chromatographic column followed by the mass transfer phenomenon between the solid adsorbent and the liquid phase. The mass transfers were represented by two lumped kinetic mechanisms, without (linear type) and with maximum adsorption capacity (Langmuir type). The simulation results show good agreement between the front velocity modeling approach and the pulse experiments both for glucose and fructose in terms of concentration along time. The lumped mass transfer Langmuir kinetic model led to peak tailings, thus showing that not only the Langmuir isotherm can lead to such profiles, but also the linear kinetic mechanism can lead to the same chromatographic behavior. The simulation results of the new front velocity approach are similar to those obtained from classic convection-dispersion models with axial dispersion coefficients. Such modeling approach can be used as a powerful tool to determine the chromatographic behavior of a sample because it can be easily implemented for routine analysis and it requires a lower number of parameters.
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