Effect of Sublimation Treatment on the Catalytic Performance of MFI Catalysts in Pyridine and 3-Picoline Synthesis

✍ Scribed by F. Jin; G. Wu; Y. Li

• Publisher: John Wiley and Sons
• Year: 2011
• Tongue: English
• Weight: 382 KB
• Volume: 34
• Category: Article
• ISSN: 0930-7516
• DOI: 10.1002/ceat.201000423

✦ Synopsis

Abstract

Mordenite framework inverted (MFI)‐structure catalysts with framework trivalent metal cations and extra‐framework metal cations were prepared by the sublimation method to synthesize pyridine and picolines. The results show that the sublimation treatment of volatile metal halides, i.e., GaCl~3~ and FeCl~3~, consumes the silanol groups of the parent sample. Most of the Ga cations are incorporated into the zeolite framework, which produces hydroxyl groups and dramatically enhances the proportion of Brönsted acid sites. At the same time, a large number of Fe cations exist in the extra‐framework, causing an increase in the proportion of Lewis acid sites. The increased acid amount and strength effectively improve the activity and stability of the catalyst. Moreover, the generated stronger acid sites increase the selectivity of pyridine. The Ga cations of the modified zeolite can promote the dehydrogenation step for pyridine synthesis, which markedly increases the pyridine selectivity.