Efficient regeneration of Pd-SSZ-13 catalysts deactivated by alkali metals for passive NO _<i>x</i> adsorption.

ABSTRACT: Pd-loaded CHA zeolites (e.g., Pd-SSZ-13) have been identified as a promising candidate for passive NO _x adsorption (PNA) in low-temperature environments. The inclusion of lubricant oil additives or biofuels in automotive exhaust after-treatment systems subjects Pd-SSZ-13 to chemical poisoning from contaminants such as alkali metals (e.g., Na and K). In this study, we present a straightforward yet highly effective approach to regenerate Pd-SSZ-13 that has been poisoned by alkali metals, achieved through washing with a dilute NH₄Cl solution. The underlying mechanisms of both poisoning and regeneration were thoroughly explored, revealing that the deactivation due to alkali-metal poisoning is primarily attributed to the transformation of the active Pd

SUBMITTER: Chen D 

PROVIDER: S-EPMC12757939 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature