Exhaled Anesthetic Xenon Regeneration by Gas Separation Using a Metal–Organic Framework with Sorbent-Sorbate Induced-Fit

Noble gas xenon (Xe) is an excellent anesthetic gas, but its rarity, high cost and constrained production prohibits wide use in medicine. Here, we have developed a closed-circuit anesthetic Xe recovery and reusage process with highly effective CO₂-specific adsorbent CUPMOF-5 that is promising to solve the anesthetic Xe supply problem. CUPMOF-5 possesses spacious cage cavities interconnected in four directions by confinement throat apertures of ~3.4 Å, which makes it an ideal molecular sieving of CO₂ from Xe, O₂, N₂ with the benchmark selectivity and high uptake capacity of CO₂. In situ single-crystal X-ray diffraction (SCXRD) and computational simulation solidly revealed the vital sieving role of the confined throat and the sorbent-sorbate induced-fit strengthening binding interaction to CO₂. CUPMOF-5 can remove 5 % CO₂ even from actual moist exhaled anesthetic gases, and achieves the highest Xe recovery rate (99.8 %) so far, as verified by breakthrough experiments. This endows CUPMOF-5 great potential for the on-line CO₂ removal and Xe recovery from anesthetic closed-circuits.