The research presented in this poster focuses on developing a metal-embedded carbon molecular sieve (CMS) based reactor for sustainable NH₃ synthesis. NH₃ is an important raw material for fertilizer production and a potential vector for H₂ storage and transport; however, it is traditionally produced via the Haber-Bosch process, which is highly energy-intensive and accounts for approximately 1.8% of global CO₂ emissions. Catalytic membranes could play an important role in the equilibrium-limited reactions involved in NH₃ synthesis, thereby reducing energy consumption and enhancing both conversion and production yields. CMS membranes, synthesized via high-temperature pyrolysis of fluorinated polyimide precursors, have been demonstrated as high-performance gas separation membranes due to their bimodal pore size distribution, which could enable the separation of NH₃ from a mixture of NH₃/H₂/N₂. In this study, a specific metal, such as Fe, was crosslinked into the polyimide structure prior to pyrolysis at 550℃ under an inert atmosphere, resulting in Fe-embedded CMS membranes. The incorporated Fe acts as a catalytic site, while the CMS membrane itself enables the separation of NH₃ from the H₂/N₂ mixture. Additional tests, including permeation, sorption, and diffusion coefficients, were performed at 35℃ to investigate the unusual transport behavior of NH₃. The results indicate that NH₃ molecules exist as clusters (NH₃)ₙ (n>1), leading to an increase in effective size (>4 Å), or causing NH₃ to incur an entropic penalty during its passage through the rigid CMS membrane structure. These analyses serve as guidelines for optimizing membrane conditions, such as exploring different pyrolysis parameters, to address observed challenges. In this talk, characterization techniques, such as BET physisorption and ICP-OES, will be presented to elucidate the structural differences between non-metal CMS membranes and Fe-embedded CMS membranes.