Significant enhancement in CH4/N2 separation with amine-modified zeolite Y

Abstract Adsorption based process for CH4/N2 separation is promising and attractive while it remains a challenge endeavor due to the lack of efficient adsorbents. In this work, amine ion-exchanged Y zeolites were developed for CH4/N2 separation. By simple ion-exchanged with tetramethylammonium cation (TMA+) and choline cation (Ch+), CH4 adsorption amounts of the resulting adsorbents were obviously increased while their N2 adsorption amounts were significantly decreased. Consequently, CH4/N2 separation performances of resulted samples were greatly improved compared to pristine NaY. CH4/N2 selectivities of resulting sample TMAY and ChY were up to 6.32 and 6.50, respectively, at 25 °C and 100 kPa. Monte Carlo calculations were used to study the interaction affinity for CH4 and N2 on the adsorbents. Breakthrough experiments were further confirmed the excellent separation performances of TMAY and ChY. The excellent separation performances of the resulting adsorbents verified the efficiency of the simple ion-exchange strategy and the application potential of the adsorbents.