Collect. Czech. Chem. Commun. 2007, 72, 618-628

Synthesis of Pyridines Over Zeolites in Gas Phase

Marek Slobodníka, Milan Hroneca,*, Zuzana Cvengrošováa, Martina Bejblováb and Jiří Čejkab

a Department of Organic Technology, Faculty of Chemical and Food Technology, Slovak University of Technology, Radlinského 9, 812 37 Bratislava, Slovak Republic
b J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejškova 3, 182 23 Prague 8, Czech Republic


Pyridine and its methyl derivatives were synthesized in vapor phase from ethanol, formaldehyde and ammonia over zeolites H-ZSM-5, Beta, mordenite and over SiO2. Both the Si/Al molar ratio and modification of zeolite with zinc strongly influenced the selectivity in pyridine and alkylpyridines formation. The highest yield of pyridine was obtained over ZSM-5 modified with zinc and the highest pyridine-to-alkylpyridines ratio was achieved over H-ZSM-5 with high Si content (Si/Al ratio 140). The conversion of ethanol and the selectivity in pyridine formation were correlated with the acidity of used catalyst.

Keywords: Pyridine; Pyridine bases; ZSM-5; Ethanol; Gas-phase reactions; Heterogeneous catalysis; Zeolites; Acidity.

References: 10 live references.