Investigation of H2S separation from H2S/CH4 mixtures using functionalized and non-functionalized vertically aligned carbon nanotube membranes

► Vertically aligned carbon nanotubes synthesized in five AAO templates and characterized. It was found that the structures of CNTs grown in AAO substrates are different and depend on the geometry of AAO channels. ► Functionalized and non-functionalized CNT/AAO membranes were fabricated and characterized. ► Performance of functionalized and non-functionalized CNT/AAO membranes for separation of H2S from binary mixtures of H2S/CH4 was investigated and compared. ► Selectivity of the CNT/AAO membrane was increased about 1.5-2.0 times after functionalization with dodecyleamine.