Journal
SEPARATION AND PURIFICATION TECHNOLOGY
Volume 315, Issue -, Pages -Publisher
ELSEVIER
DOI: 10.1016/j.seppur.2023.123725
Keywords
Polyimide; Membrane; DDSQ; Nanocomposite; Gas separation
Categories
Ask authors/readers for more resources
In this study, a series of DDSQ-based polyimide membranes with intrinsic microporosity (PIM-PIs) were synthesized and fabricated, showing desirable mechanical properties, heat resistance, and gas permeability. Among all membranes, DDSQ-25 and DDSQ-50 exhibit the most favorable gas separation performance, almost achieving the 1991 Robeson upper bound.
Membrane-based gas separation technique shows great potential in CO2 elimination from natural gas and N2 enrichment from compressed air. In this study, a double-decker-shaped phenyl-substituted silsesquioxane (DDSQ)-based diamine monomer, that is, DDSQ-diamine, was synthesized and subsequently copolymerized with 4,4 '-(hexafluoroisopropylidene) diphthalic anhydride (6FDA) in combination with 4,4 '-oxydianiline (ODA) to fabricate a series of DDSQ-based polyimide membranes with intrinsic microporosity (PIM-PIs). The resulting membranes showcase desirable mechanical robustness, satisfactory heat resistance and good organo solubility. Owing to the inherent internal nanometer-sized cavity of DDSQ cage, DDSQ-based membranes are more nanoporous than DDSQ-free sample, accordingly exhibiting decreasing membrane density and increasing gas permeability. Among all membranes, DDSQ-25 and DDSQ-50 show more desirable overall gas separation per-formance, which almost achieve the 1991 Robeson upper bound. Additionally, DDSQ-25 demonstrates good plasticization resistance and CO2/CH4 mixed-gas separation properties when measured with 50:50 CO2/CH4 binary gas mixture at upstream pressure up to 20 bar. Despite physical aging at ambient conditions for 300 days, the resultant DDSQ-based polyimide membranes still have stable gas permeability and almost constant selec-tivity, showcasing satisfactory anti-aging characteristic.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available