A Tutorial on Membrane Permeation

The separations of CO2/H2, CO2/CH4, CO2/N2 and other gaseous mixtures are of practical importance for CO2 capture and other applications in the processing industries. Use of membranes with microporous layers of zeolites, metal organic frameworks (MOFs), and zeolitic imidazolate frameworks (ZIFs) offer considerable promise for use in such separations. In view of the extremely wide variety of available microporous structures, there is a need for a systematic screening of potential candidates in order to obtain the best permeation selectivities, Sperm. The permeation selectivity is a product of the adsorption selectivity, Sads, and the diffusion selectivity, Sdiff. We have identified two different classes of materials that have different permeation characteristics.
Consult also my papers for background theory
[1] R. Krishna, Using the Maxwell-Stefan formulation for Highlighting the Influence of Interspecies (1-2) Friction on Binary Mixture Permeation across Microporous and Polymeric Membranes, J. Membr. Sci. 540 (2017) 261-276. (doi.org/10.101...)
[2] R. Krishna, J.M. van Baten, Influence of Adsorption on the Diffusion Selectivity for Mixture Permeation across Mesoporous Membranes, J. Membr. Sci. 369 (2011) 545-549.
[3] R. Krishna, J.M. van Baten, In Silico Screening of Zeolite Membranes for CO2 Capture, J. Membr. Sci. 360 (2010) 323-333. (doi.org/10.101...)
[4] R. Krishna, J.M. van Baten, Fundamental Insights into the Variety of Factors that Influence Water/Alcohol Membrane Permeation Selectivity J. Membr. Sci. 698 (2024) 122635. (doi.org/10.101...)
[5] R. Krishna, J.M. van Baten, Using the Spreading Pressure to Inter-Relate the Characteristics of Unary, Binary and Ternary Mixture Permeation across Microporous Membranes, J. Membr. Sci. 643 (2022) 120049. (doi.org/10.101...)