Productivity Considerations and Design Charts for Biomolecule Capture with Periodic Countercurrent Adsorption Systems

General design charts are presented to enable the prediction of the steady state performance of periodic countercurrent adsorption systems for conditions typical of biomolecule capture on selective adsorbents. The underlying model assumes that the process is controlled by diffusion in the intraparticle macropores and that the adsorption equilibrium can be described by the Langmuir isotherm. Model results are presented in dimensionless form for isotherms ranging from highly favorable to nearly linear. When the isotherm is highly favorable, operating with 2 to 3 columns in series reduces the amount of adsorbent needed by 15 to 35% when the process is operated with a rapid cycle. Smaller improvements are predicted for longer cycles, while larger improvements are predicted when the isotherm is less favorable. Increasing the number of columns in series beyond 2 or 3 is probably unwarranted since incremental improvements decline rapidly going from 2 to 3 columns. Use of the charts is illustrated with a specific example of application to a protein A capture system.