Analysis of flow profiles and mass transfer of monolithic chromatographic columns: the geometric influence of channels and tortuosity

Abstract

Several modeling techniques have been applied to describe mass transfer and adsorption in a cryogel column for chromatographic separations. Nevertheless, complex boundaries of this spongy matrix where the fluid dynamics, mass transport and reaction equations render such simulations of high computational resource requirements. Thus, this work proposed a fast-solving and robust simulations to analyze the field velocity and the concentration/adsorption profiles in unsteady state varying flow velocity and axial dispersion. Four proposals for monolith geometry with distinct tortuosities were suggested to evaluate the influence of channel architecture on transport phenomena. Breakthrough curves predicted by the Navier Stokes equations for monolithic channels were compared with those predicted by the Darcy equations for the cryogel column. The CFD model can be accepted as the soft sensor with feasible descriptions of more complex models. Experimental and predicted breakthrough curves presented good correlation with R2 values of 0.99 for channels in the triangular format and tortuosity of 1.12, which represented the monolithic architecture properly.