From Reactive Distillation To Reactive Membrane Separation: A Generalized Approach For Feasibility Analysis

A new feasibility analysis methodology generalized from distillation is applied to membrane process. The model is formulated to depict the reactive liquid phase composition on the retentate side of membrane reactors. The effects of both chemical reaction and membrane mass transfer kinetics on the feasible products are elucidated by means of retentate phase diagrams and bifurcation analysis. In the proposed method, the description of flux induced by selective mass transfer effects is subordinate so that the method can be applied to various membrane processes, providing that the flux equation is acquired either by applicable diffusion theories or by experimental membrane characterization. Some examples of ternary and quaternary systems are introduced to illustrate the methodology. It is shown that the selective mass transfer through membranes can change the topology and stationary points of the retentate phase diagrams. This implies the desired products which are not attainable in open distillation can be feasible by means of suitable membranes. Furthermore, a new set of composition variables is introduced to transform the original model equations into an analogous form of open distillation, and leads to the explicit conditions for singular points in membrane process, which are termed as reactive arheotropes.