Synthesis of pyridine and picolines over modified silica-alumina and ZSM-5 catalysts

Abstract

In the reaction of acetaldehyde, formaldehyde and ammononia over HZSM-5 (Si/Al-280), PbZSM-5 and WZSM-5 catalysts at 420°C, 0.5 h^-1 weight hourly space velocity, the total yields of pyridine and 3-picoline obtained were 58.2, 42.8 and 78.3 wt.% based on aldehydes, respectively. In the reaction of acetaldehyde and ammonia over typical Pb-SiO₂-Al₂O₃ (20% PbO), W-SiO₂-Al₂O₃ (10% W), Pb-Cr-SiO₂-Al₂O₃ (F) and Pb-Cu-SiO₂-Al₂O₃ (E) catalysts at 420°C, 0.5 h^-1 W.H.S.V., the yields of 2- and 4-picolines obtained were 51.1, 66.1, 80.6 and 53.7 wt.%, respectively.