(227a) Bench-Scale Direct Air CO2 Capture Modules Based on Amine-Infused Fiber Sorbents

The deployment of advance direct air CO₂ capture (DAC) contactors is essential for achieving low pressure drops and reducing energy consumption of the process. Increasing volumetric productivity by shortening the recyle time is also important for cutting the leverage cost of CO₂ capture (LCOC). In this work, two DAC modules with distinctive heat exchange configurations, namely "shell & tube" (S&T) and "plate & frame" (P&F), were fabricated using 3D printing to house bundles of PEI-infused fiber sorbents and nonwoven laminates made from these fiber sorbents, respectively. Heat transfer analysis and CO₂ desorption experiments indicate that the P&F configuration afford better heat transfer efficiency and much faster CO₂ desorption kinetics compared to the S&T module. Pressure drop measurement suggests that optimal module designs enable low pressure drops (< 11 Pa/cm) at high air speed (~ 3 m/s) required by practical DAC processes. Long-term performance evaluation of the fiber sorbents highlights the importance of choosing appropriate polymer materials that are compatible with the active CO₂ sorption sites in the sorbents. In summary, this study showcases an attractive path forward for reducing DAC sorbent costs by using fiber sorbents from readily available materials and demonstrates the significance of proper engineering of modular DAC devices to achieve desirable DAC performance.