WAVE-PROPAGATION IN MASS-TRANSFER PROCESSES - FROM CHROMATOGRAPHY TO DISTILLATION

This article reviews the advancement of the dynamic theories based on wave propagation phenomena for two major classes of separation processes: fixed-bed sorption processes such as chromatography and countercurrent mass-transfer processes such as distillation. Aiming at providing a common perspective, this article begins with a brief review of the fundamental physics of wave propagation in these processes with notations common to both classes. Then, for single-variance systems (with one independent component), it reviews the well-developed theories for fixed beds and, as the main focus, the recent efforts to adapt these theories to countercurrent processes, in particular, distillation. The last part reviews the equilibrium theories of multicomponent chromatography with emphasis on the coherent wave theory originated by Helfferich and briefly covers the most recent attempts to apply this theory to multicomponent countercurrent processes. The review is summarized with prospects of applying the wave propagation theory to distillation control and design.