This review gives an overview of the key results in various fields of membrane technology with special emphasis to their exploitation in sustainable industrial applications. Considerable progress has been made in short time in a number of important application areas: membrane technology and engineering for water treatment, gas separation, purification and recovery in petrochemical, chemical, pharmaceutical, electronic industry, regenerative medicine etc. The basic properties of membrane operations (generally a-thermal; simple in concept and operation; modular and easy to scale-up; with a potential for more rational utilization of raw materials and recovery and reuse; compatible to a retrofit strategy) are at the basis of their integration into industrial practice.

The intrinsic characteristics of a membrane process, i.e. efficiency and operational simplicity, high selectivity and permeability for the transport of specific components, compatibility between different membrane operations in integrated systems, low energetic requirements, easy control and scale-up, and high operational flexibility, might be decisive factors in imposing membrane processes in most gas separation fields. This review highlights the research hardware in membrane gas separation, i.e. the membrane material. Emphasis has been devoted to three interesting and important membrane classes for gas separation: block copolymer membranes, carbon membranes and mixed matrix membranes.