Effect of aluminium acetyl acetonate on the hydrogen and nitrogen permeation of carbon molecular sieves membranes

With a growing interest in hydrogen as energy carrier, the efficient purification of hydrogen from gaseous mixtures is very important. This paper addresses the separation of hydrogen using Carbon Molecular Sieves Membranes (CMSM), which show an attractive combination of high permeability, selectivity and stability. Supported CMSM containing various amounts of aluminium have been prepared from novolac and aluminium acetyl acetonate (Al(acac)(3)) as carbon and alumina precursors. The thickness of the CMSM layers depend on the content of Al(acac)(3) in the dipping solution, which also has influence in the pore size and pore size distribution of the membranes. The permeation properties of the membranes against the Al content in the membrane follows a volcano shape, where the membrane containing 4 wt (%) of Al(acac)(3) has the best properties and was stable during 720 h for hydrogen at 150 degrees C and 6 bar pressure difference. All the CMSM have permeation properties well above the Robeson Upper limit. (c) 2022 The Author(s). Published by Elsevier Ltd on behalf of Hydrogen Energy Publications LLC. This is an open access article under the CC BY license (http://creativecommons.org/ licenses/by/4.0/).

Automated summary

This study focuses on the separation of hydrogen using Carbon Molecular Sieves Membranes (CMSM), with membranes containing 4% Al(acac)(3) showing the best properties and stability over 720 hours at 150 degrees C and 6 bar pressure difference. The permeation properties of all CMSM exceed the Robeson Upper limit.