Adsorptive Gas Separation of Carbon Dioxide from Methane by Zeolitic Imidazolate Frameworks (ZIFs)
SUMMARY
UCLA researchers in the Department of Chemistry and Biochemistry have demonstrated the ability of functionalized zeolitic imidazolate frameworks (ZIFs) to be used in gas separation processes, thereby having industrial applications in natural gas purification and landfill gas separation.
BACKGROUND
ZIFs are a class of metal-organic frameworks (MOFs) composed of metal ions connected by organic linkers. Because of the unique positioning of the metal ions and linkers, ZIFs are porous in nature, highly stable, and therefore, having a wide range of applications. A particularly attractive application of ZIF is for its use as carbon dioxide (CO2) scrubbers in addition to other gas separation. With constant pressure from government regulations for cleaner air exhaust from industrial plants, companies are constantly faced with a need for improved air separation methods. Novel advancement in ZIF to improve its functionality and CO2 affinity will greatly improve its use in industrial plants.
INNOVATION
Dr. Omar Yaghi at UCLA has generated two novel ZIFs (ZIF-20 and ZIF-35) with adsorbent capabilities and has been demonstrated to have 5-times higher affinity for CO2 compared to methane gas (CH4). The ZIFs are currently being modified for applications towards other gas mixtures.
APPLICATIONS
• Landfill gas separation
• Natural gas purification
• Fuel Storage
ADVANTAGES
• The functionalized ZIF have 5 times higher affinity for CO2 compared to CH4
• ZIF are easily adaptable towards other gas separation and purification
• ZIF require very little energy to create and highly stable
STATE OF DEVELOPMENT
Separation of CO2 from CH4 in a 50/50 mixture has been successfully demonstrated with ZIF-20 and ZIF-35.