9. Conclusion

Gas permeation is the latest development in gas mixture separation, and is now one of the mature technological solutions traditionally considered for industrial applications. While the portfolio of materials and modules available, and the types of applications currently envisaged, remain relatively limited and confined to membranes based on dense polymers, recent developments in nanostructured materials, as well as spectacular progress in thin-film production techniques (including additive manufacturing), point to breakthrough developments in the years to come. By way of example, the existence of commercial zeolite-based modules or even the recent appearance of reactive industrial membranes (for CO ₂ capture) could reflect a significant change in the landscape. While polymeric materials have proved their worth in terms of performance (and are...