Production of carbon-neutral fuels is a significant challenge to reduce greenhouse gas emissions from the energy sector. In this regard, microporous ceramics such as Zeolites, aluminophosphates, silicoaluminophosphates, and activated carbons hold great potential for decarbonizing gas streams. These microporous ceramics requires tailoring of porosity at various length scales to optimize their properties for the economical decarbonization of gas streams. The recent developments on tailoring porous structure and evolution of properties required for CO2 separation from power-plant flue gas and raw biogas, including CO2 uptake capacity, high CO2 over CH4 and CO2 over N2 selectivity, rapid uptake and release kinetics, and long-term durability will be discussed. We will demonstrate that novel approaches such as binderless processing, nanostructurization and electrospinning can produce novel structured materials for economically producing biomethane for small scale and large-scale raw biogas plants. For CO2 utilization, the structuring of metal-zeolite and MOF-derived catalysts will be presented.