Saf ve iyonik sıvı i̇çerikli metal organik kafesli yapılarda CH4 adsorpsiyonunun deneysel ve hesaplamalı olarak i̇ncelenmesi

Natural gas is an abundant and relatively clean energy source with a potential to replace petroleum towards a low-carbon energy future. The most challenging part of utilizing natural gas for various applications is the development of a feasible method for its high density storage. Natural gas is commonly stored as compressed or liquefied natural gas which both create economical and safety issues. An alternative approach for safe and efficient storage of natural gas, adsorbed natural gas (ANG), has drawn attention recently. For the efficient implementation of ANG specifically tailored high capacity adsorbents are required. Metal organic frameworks (MOFs) have emerged as crystalline porous materials constructed from organic linkers and metal clusters. MOFs are considered as very promising adsorbents as a result of their extraordinary structural characteristics, such as high surface area, high porosity, low density as well good thermal and mechanical stability. In the first part of this thesis, grand canonical Monte Carlo (GCMC) simulations were performed to investigate CH4 (main component of natural gas) storage performance of MOFs. Structural/chemical properties of MOFs were calculated and simple multivariate linear models were constructed to predict CH4 uptake of over 1500 different MOF structures using these properties. Moreover, the structural/chemical characteristics resulting in high CH4 uptake were identified and optimum ranges for these properties were presented. In the second part, experimental characterization and high pressure adsorption measurements for CH4, CO2, N2, and H2 were performed for one of the top performing MOFs, HKUST-1 (commercially available as Basolite C300). Incorporation of ionic liquids (ILs) were examined using 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4]) to enhance gas storage and separation capabilities of Basolite C300. Results suggest that incorporation of ILs in MOFs results in modified adsorption capacities for different gases, with the highest affinity towards CH4. The high pressure gas storage capacities were lowered with the addition of IL however, improved gas separation performance was observed. As a result, IL-incorporated MOFs are identified as new type of adsorbents with high potential for various gas storage/separation applications.