(167h) Operation Strategies for Chromatographic Separation Processes with Reduced Purity Constraints

Preparative and large scale chromatographic separations have been traditionally designed to yield pure products, i.e., purity = 100%. However, several practical applications exist where only a partial enrichment is expected from the chromatographic step. This area has so far received limited attention from the perspective of process design. This presentation seeks to address this important problem.

A number of operating strategies have been identified to improve the performance of chromatographic single column and multicolumn (simulated moving bed) separation processes. In this contribution, we analyze such strategies theoretically (equilibrium theory) and by means of numerical simulations. It is demonstrated how the objective (maximum productivity, minimum eluent consumption), design constraints (purity, yield), and achievable separation efficiency affect the choice of the optimal strategy. Most of the strategies discussed can be implemented without any additional equipment or columns thereby making them attractive for practical applications. Further, depending on the objectives of the separation, it is shown that each operational strategy shows characteristic advantages, and a general guideline to choose a particular configuration is illustrated. Finally, methods for designing these processes are discussed.