3423.     ---------------.  [TRAMBOUZE, Y.]  [Chemical Changes in Fischer Catalysts During Their Preparation.]  Jour. chim. phys., vol. 47, 1950, pp. 258-261; Chem. Abs., vol. 44, 1950, p. 7638.

        Ni, Al, Mn, kieselguhr catalysts were prepared by the following methods, and the % of the Ni removed by ammoniacal treatment, extraction with HNO₃, and with HCl, respectively, are:  Precipitation at low temperature 100, ----, ----; boiling of the precipitate, 63, 37, ----; desorption under vacuum at 150° to constant weight, 63, 37, ----; heating for 2 hr. at 220° in N₂, 59, 13, 28; heating at 320° to constant weight in N₂, 18, 46, 36; heating at 450° to constant weight in N₂, 16, 40, 44; heating for 48 hr. at 220° in N₂, 33, 59, 8; heating at 450° after the preceding treatment, 20.5, 59.5, 20.  An X-ray diffraction study of these catalysts is summarized.