Fluorine-enhanced Pt/ZSM-5 catalysts for low-temperature oxidation of ethylene

Abstract

The low-temperature oxidation of ethylene (C₂H₄) is of critical importance in some specific places and environments such as refrigeration storage, but the catalyst stability needs to be further improved. The microporous Pt/ZSM-5 catalyst prepared in this study exhibited excellent catalytic performance in C₂H₄ oxidation. The modification of F on Pt/ZSM-5 was further investigated to explore the possibility of enhancing the catalytic performance for low-temperature oxidation of ethylene. Compared with unmodified Pt/ZSM-5 catalyst, the F modification has efficiently improved the reaction stability of the Pt/ZSM-5 catalyst. The conversion of C₂H₄ over 0.5% Pt/F-ZSM-5 could be sustained at 100% for more than 11 h at 25 °C. This study showed that the acidity and water tolerance of catalysts were crucial factors that affected the catalytic stability. The enhancement of the Brønsted acidity of the F-treated ZSM-5 was favourable for the adsorption and activation of C₂H₄ molecules onto the Pt/F-ZSM-5 catalysts. The F modification prolonged the catalyst life by improving its water tolerance. Thus, Pt/F-ZSM-5 has the potential to be an efficient low-temperature catalyst for C₂H₄ elimination in possible applications.