Enhanced F-Gases’ Recovery by Introducing Lewis Acid Sites into MFI Zeolites

The development of efficient adsorbents for perfluorinated electronic specialty gases’ (F-gases) recovery presents significant challenges in the chip plasma etching process. In this study, we focus on preparing Ti- and W-replaced MFI zeolites, which offer abundant Lewis acid sites, to enhance the separation of F-gases toward N2. Through single-component gas adsorption and ideal adsorbed solution theory selectivity analyses, the Ti- and W-doped MFI zeolites demonstrate remarkable separation performance. Additionally, dynamic breakthrough experiments have confirmed the effective capture of F-gases using Ti- and W-doped MFI zeolites. The intrinsic adsorption mechanism was also investigated by the Grand Canonical Monte Carlo and independent gradient model (IGM) simulations. IGM results indicate that there is a strong charge transfer interaction between the polar Lewis acid sites in the MFI channel and F-gases with high polarizability. These results highlight the promising potential of MFI zeolites with abundant Lewis acid sites for addressing F-gas capture in the semiconductor industries.