3779. ----- [UNION CHIMIQUE BELGE]. [Exothermic Catalyst synthesis in Gaseous Phase.] Belgian Patent 360,405, June 29, 1929. Chem. Abs., vol. 24, 1930, p. 903.

Catalysis is carried out in successive and progressive stages, the amplitude of each stage being regulated so that at no point in the mass is a given predetermined temperature exceeded. The vertical walls of the vessel containing the catalyst are provided with horizontal protuberances is provided with openings for partial successive introductions of fluid.