Development of heterogenous capillary membranes with programmable properties made of PEBA copolymer for CO2 removal and testing their properties.

The process of membrane gas separation is a technique of increasing interest in industrial applications. In many cases, the membrane gas separation process can replace or support commonly used technologies for gas mixtures separation, such as adsorption, absorption or cryogenic distillation. One of the areas in which the research on the development and implementation of new types of membranes is particularly intensive is the technology of CO₂ removal from mixtures containing also CH₄ or N₂. The need to extract CO₂ from these mixtures results from economic, legal, ecological and technological reasons. A solution that can improve the process properties of membranes is the development of heterogeneous membranes. Heterogeneous membranes are structures consisting of a polymeric continuous phase and an organic or inorganic dispersed phase. The presence of additives can improve both the permeability of the membrane and its selectivity, as well as the mechanical properties. However, in addition to developing a new material and examining its properties, it is also necessary to propose a method for manufacturing membranes from these materials on an industrial scale and to determine their process properties based on tests on gas mixtures. For this purpose, heterogeneous capillary membranes obtained by dip coating method were developed. PEBAX® 2533 copolymer and additives such as SiO₂, zeolitic imidazolate frameworks (ZIF-8) or PSS-octaphenyl substituted (POSS-Ph) were used to produce them. The permeability and selectivity of the developed membranes were determined on the basis of tests using pure gases (CH₄, CO₂ and N₂), as well as gas mixtures (CO₂/CH₄ and CO₂/N₂). The process conditions used in the research, that is, feed pressure and temperature, were determined on the basis of the authors' previous research [1] and mathematical-statistical analysis. On the basis of the conducted tests, the usefulness of the produced composite capillary membranes for conducting the process of separating gas mixtures in which CO₂ is one of the components has been proven. [ABSTRACT FROM AUTHOR]