(663a) CO2 Capture and Transport Behaviors of Porous Polymer Beads Containing Metal-Organic Frameworks (MOFs)

A number of novel materials including metal-organic frameworks (MOFs) have been developed to capture CO₂ from various industrial sources. While some recently synthesized MOFs have great CO₂ capture capacity and even water tolerance, their delivery method is still debated. For example, MOFs can be used in the perm-selective layer of gas separation membranes. The direct use of MOFs is not desired due to the safety and process concerns related to fine powder handling. In this study, MOFs-bearing porous polymer beads are prepared and their CO₂ adsorption behaviors are studied in a fixed bed and a fluidized bed reactor. CO₂/N₂ and CO₂/CH₄ gas mixtures are used as the inlet gas and the CO₂ capture conditions are maintained at ambient condition (25 ^oC and 1 atm) while varying the gas velocity to obtain CO₂ breakthrough curves. The experimental findings suggest that the CO₂ adsorption kinetics of MOFs-bearing porous polymer beads are very fast and this delivery method of MOFs can allow for a flexible design of CO₂ capture units ranging from a fixed bed to a fluidized bed. The effect of moisture on the CO₂ adsorption behavior is also investigated while changing the chemical properties of the porous polymer substrate (e.g., hydrophilic vs. hydrophobic). The recyclability of the beads is determined via repetitive long-term CO₂ adsorption and desorption experiments where the partial pressure of CO₂ is controlled as well as humidity.