ピリヂン同族体の接触気相酸化 (第3報)

α-ピコリンの接触酸化について

抄録

1) In the preparation of pyridine from α-picoline with V₂O₅-pumice stone as a catalyst, studies were made to find the relationship between the amount of catalyst and the yield. Using reaction tube with section area of 2.0cm², a mixture of α-picoline and air are passed at a flow rate of 0.05cc/min., and 300cc/min., respectively, and the best yield of pyridine was obtained at the thickness of catalyst layer of 7.5-15cm. Catalyst layer of more or less than this thickness decreased the yield.
2) If the methyl group in α-picoline alone received partial oxidation to give pyridine, then the amount of oxygen necessary would be 1.5mol. oxygen per mol. of picoline. Actually, however, partial oxidation of pyridine ring occurs at the same time that the amount of air most suitable is 3.5-6 liter per 1cc. of α-picoline, i.e. about 2-3.5 times more air than the theoretical amount.
3) Comparison of resistance to oxidation between α-picoline and pyridine showed that the former is more liable to oxidation at a lower temperature.