Application of Nanoparticle-Doped MOF Composite-Embedded Mixed Matrix Membranes in Carbon Capture

Carbon dioxide (CO2) is released into the atmosphere from both natural sources and human activities. In Turkey, the largest source of CO2 emissions from human activities is energy, industrial processes and product use, agriculture, and waste. According to the National greenhouse gas (GHG) Emission Inventory Report, which covers the years 1990-2020 submitted under the United Nations Framework Convention on Climate Change, the energy sector accounted for 85.4% of total CO2 emissions in 2020. Total CO2 emissions from all sectors have increased by approximately 173% in 30 years. Thus, CO2 constitutes 86% of total GHG emissions in Türkiye. This situation shows that capturing CO2, which is a major contributor to large-scale GHG emissions, requires new technologies and resources that can operate in an economically viable manner. In this context, carbon capture technologies, which are categorized as pre-combustion, post-combustion, oxyfuel combustion, and direct air capture, have been intensively studied by researchers in recent years. According to current studies, post-combustion capture technologies, which involve the separation, capture, and storage of CO2 from flue gas after combustion, have been an approach explored more. However, it is also unsurprising that the CO2 capture process, which is complex and energy-intensive, varies depending on specific emission sources. The most common post-combustion capture approaches are cryogenic separation of CO2 from other gases, the use of selective membranes, electrochemical separation, physical and chemical absorption in liquid solvents, and adsorption on solids. Among these technologies, membrane-based CO2 separation processes stand out and new studies are required to develop membranes with high CO2 selectivity and permeability. In this context, metal-organic frameworks (MOFs) are candidates to meet the need for an effective CO2 capture material due to their superior properties. The mixed matrix membranes (MMM), which will be developed by incorporating nanoparticle-doped MOFs into conventional membranes, will provide CO2 selectivity in a gas mixture. Thus, an MMM with high porosity, high CO2 selectivity, economic feasibility, and thermal and water stability can be obtained by incorporating a MOF composite.