The application domains for zeolites continue to expand in the face of new process targets, driven by the need for feedstock flexibility and by emissions mandates. Realizing the full potential of zeolite-based catalyst and adsorbent technologies at scale requires continued advances in our understanding and control of local structure at different points in the zeolite lifecycle – from the crystallization process in which the zeolite forms, to the working conditions under which it is deployed.

In this talk, we show that two distinct local structural features challenge conventional views of what governs nucleation during zeolite synthesis, and what governs hydrophilicity in adsorption applications. During crystallization, we demonstrate how the typical dependence between organic structure-directing agent (OSDA) quantity and nucleation efficiency inverts in SSZ-13 (CHA) in the presence of a small quantity of cyanuric acid (CA). We trace this to the CA-driven, atomic-scale restructuring of the amorphous intermediate leading up to nucleation, the degree of which depends on OSDA loading. In fully crystalline zeolites, we show how certain confining environments break the usual tradeoff between CO₂ capacity and CO₂/H₂O selectivity, typically set together by Si/Al, that limits benchmark CO₂ adsorbents such as 13X under humid conditions. We find that the robust performance of MER and KFI originates from linear CO₂ binding to cations in confined cages, while H₂O interacts more weakly with cations and more strongly with itself. We expect these design strategies to extend well beyond the systems presented here.