Survey of Membrane Separation Models

Abstract

For the description of membrane permeation, many physical models have been proposed and are mainly based on thermodynamics and/or statistical mechanics, thus expressing permeation rates by parameters derived from bulk properties. Several authors relate the sorption and transport phenomena to molecular properties such as rigidity of polymer backbones, types of pendant group, molecular packing density, and interactions with polar groups,^{20, 21} but this is all still very qualitative. Of course, the latter route represents the most fundamental scientific approach. However, calculating molecular dynamics is still a long way off. Up to the present the thermodynamic/statistical approach is the most practical procedure.