Chapter 15 - MOF mixed matrix membranes for CO2 separation

Abstract

The control of CO2 emissions, first, via its efficient enrichment and further sequestration or conversion, requires an affordable separation technique. In order to achieve energy-efficient processes for CO2 separation from large emission sources, a membrane-based approach offers hypothetically a higher potential for energy consumption reduction. Among various CO2-mitigation technologies, membrane-based separations have a much reduced footprint compared, for example, to sorption-based technologies. In general, polymeric and inorganic membranes have been investigated in gas separation studies which have their own advantages and inconveniences. The main problem facing membrane-based technologies is the trade-off between selectivity and permeability. Accordingly, focus was directed to other materials to make membranes, such as zeolites and metal-organic frameworks (MOFs). In spite of the high degree of order and porosity, MOFs have limitations in terms of their processability as a thin-film membrane. As an alternative solution, research has been ongoing to use MOF as fillers in the fabrication of a new type of mixed matrix membranes (MMMs) by incorporation of MOF fillers into polymer matrices. In this chapter, we will give an overview about the last main achievements in lab scale studies for CO2 capture using MOF-based MMMs. We critically analyze the reported works and give a perspective view about opportunities and challenges.