Sorbent Regeneration via Radio Frequency Assisted Dielectric Heating for Direct Air Capture of CO2

Direct air capture (DAC) of CO2 is a negative emission technology that utilizes sorbents requiring a regeneration step for continued absorption-desorption cycles and reuse. Here, we report an unconventional approach to desorb cap-tured CO2 from a porous sorbent using radio frequency (RF) irradiation for dielectric heating and targeted energy transfer with the goal of lowering the regeneration energy requirement, enabling modularity, and promoting renew-able energy input. Regeneration of composites of functional ionic liquid and metal organic framework (IL/MOF) with high CO2 capacity, selectivity and enhanced transport are demonstrated under conditions relevant to DAC. RF-assisted dielectric heating at MHz frequency range shows effective absorption of the electromagnetic energy and consequently the rapid release of the captured CO2. This study demonstrates a low frequency electromagnetic radiation as an alter-native approach with multiple prospects of tunability for energy efficiency in DAC.