Comparative investigation on the correction factors of hydrogen permeability on CNTs-Mixed matrix membrane

This paper discusses different important gas permeation models such as “Maxwell”, “Bruggeman”, “Lewis-Neilson”, and “Pal” models to predict “Mixed Matrix Membranes” (MMMs) performance. The main parameter considered and discussed is the permeability of Hydrogen on Carbon Nanotubes (CNTs)-MMM. For evaluation of the theoretical models, experimental data of permeability for H۲ were compared to the theoretical models. The results revealed that, the existing models are not appropriate for evaluation of the permeability of the carbon nanostructure-based MMMs. Therefore, correction factors are needed to fit the selective permeability of carbon nanostructure-based MMMs for selective separation of various gaseous such as H۲ or CO۲. This correction factor robustly depends on the morphology of carbon nanostructures, the defect, kind and amount of metal/metal oxide nanoparticles, doped on carbon substrate and functional groups in the carbon matrix. Hence, to be in a good agreement with experimental data for separation of H۲ from CO۲, the correction value was estimated to -۰.۰۰۲۲ for single-walled carbon nanotubes (SWCNTs), -۰.۰۰۳۲ for pure multi-walled carbon nanotubes (MWCNTs), -۰.۰۰۴۴ for carbon nanofibers (CNFs).