Vapor/gas separation through carbon molecular sieve membranes: Experimental and theoretical investigation

The separation of H2O vapor from (hydrogen-rich) gaseous streams is a topic increasing interest in the context CO2 valorisation, where situ water removal increases product yield and catalyst stability. In this work, composite alumina carbon molecular sieve membranes (Al-CMSM) were prepared phenolic resin solutions loaded with hydrophilic boehmite (γ-AlO(OH)) nanosheets (0.4–1.4 wt. % solution) which partially transform to γ-Al2O3 upon thermal decomposition resin, improving hydrophilicity thus adsorption-diffusion contribution permeation. showed no influence on pore size distribution range micropores, but they increased membrane hydrophilicity. addition, use solution causes an increase viscosity layers thickness deposited porous α-Al2O3 support (from 1 3.3 μm). Furthermore, sheets introduce defects matrix, tortuosity active layer, as concluded via phenomenological modelling parametric fitting experimental results. As consequence, permeability exhibits maximum (1.3ꞏ10−6 molꞏs−1 Pa−1 m−1 at 150 °C) boehmite/alumina content ca. 0.8 %, combined effects (which favour permeability) hamper loading. Similarly, H2O/gas perm-selectivity optimum 1.2 We further investigated permeation mechanism by mono- multi-layer adsorption capillary condensation microporous media, result main transport mechanisms explored conditions.