Directly decorated CeY zeolite for O2-selective adsorption in O2/N2 separation at ambient temperature

Abstract

The traditional zeolites used in air separation are generally N₂-selective adsorbents. It was found for the first time that the O₂/N₂ adsorption selectivity can be reversed by directly decorating the Ce metal ion sites of a traditional Y zeolite with imidazole molecules, which results in a novel O₂ adsorbent. The O₂/N₂ selectivity changes from 0.9 to 1.6 under normal conditions, and most importantly, the O₂ adsorbent is recyclable. The in situ XPS characterization results indicate that the imidazole modification can change the electronic state of Ce in the Y zeolite and increase its affinity for O₂, which is confirmed by theoretical calculations. Dynamic breakthrough adsorption experiments show that the adsorbent has significant application potential in air separation.