(380s) Metal-Embedded Carbon Molecular Sieve (CMS) Membranes for Sustainable Ammonia Production

The research pertaining to this oral presentation is focused on developing a metal-embedded carbon molecular sieve (CMS) based catalytic membrane reactor for sustainable ammonia (NH₃) synthesis. This catalytic membrane is aimed at overcoming the thermodynamic limitations of NH₃ synthesis via continuous removal of NH₃ during the process. NH₃ is an important raw material for fertilizer production and traditionally it is produced via the Haber-Bosch process which is highly energy intensive and by itself accounts for ~1.8% global CO₂ emissions. Catalytic membranes, on the other hand, have the potential to reduce the energy consumption associated with NH₃ synthesis, while simultaneously ensuring high NH₃ yields. CMS membranes, synthesized via high temperature pyrolysis of polyimide precursors, have been demonstrated as high-performance gas separation membranes. In this work, their range of application will be extended beyond to reactive separation via inclusion of metals within the membrane structure. The embedded metal will be designed to act as the catalytic site , while the CMS membrane itself will enable separation of NH₃ (2.6A) from similar-sized gas H₂ (2.9A) and N₂ (3.6A) molecules. Primarily, Fe will be used as the metal, while fluorinated-copolyimides will be used as the precursor for CMS. A range of metal incorporation techniques and synthesis conditions will be analyzed and the resulting materials will be characterized in terms of both separation and catalytic properties. The separation properties will be reported in terms of permeability and sorption coefficients for NH₃, N₂ and H₂ and these results will also be used to elucidate the morphological structure of CMS. Characterization techniques to analyze the metal content and metal dispersion will be covered in the oral presentation as well.