Ketene: Acetone Vapour over Hot Porous Earthenware (Schmidlin and Bergman 1910)

Ketene, H2C:CO. Schmidlin and Bergman made it by passing acetone vapour through a hard glass tube packed with porous earthenware at 500-600 °C, with a yield of 14 %. It is a liquid only below -56 °C, smells very penetrating, and its vapour attacks the mucous membranes. Source: Thorpe, Dictionary of Applied Chemistry vol. 3 (1912), Ketenes. Unknown: the flow rate. Thorpe gives no way to catch the ketene; ours follows Organic Syntheses Coll. Vol. 3, p. 508 (1955). Fume hood and respirator are ours. Picture drawn by Youblob.