Analysis of steady state recycling chromatography using equilibrium theory

This paper presents a method for analysis and design of steady state recycling (SSR) chromatography under arbitrary purity or yield requirements. The approach applies to SSR processes in mixed-recycle operation and allows for the direct prediction of the steady state and the design parameters without performing dynamic simulations. Therefore, it simplifies optimal design of SSR processes and evaluation of process performance, while allowing minimizing the startup time of the process.It was shown that, when the purity and/or yield of the product fractions is specified, the total injection width is the only free operating parameter in mixed-recycle SSR chromatography. Theoretical analysis of the process revealed that the productivity is necessarily lower than that of an optimized separation by batch chromatography. On the other hand, the SSR process always outperforms batch chromatography in terms of eluent consumption and product concentrations.