357. CHAKRAVARTY, K. M. Catalytic Masses for Hydrocarbon Synthesis. British Patent 580,612, Sept. 13, 1946, appl. filed July 7, 1944. Chem. Abs., vol. 41, 1947, p. 2218.

Patent Abstracts

Catalytic masses, especially those containing Ni for promoting the reaction of CO and H₂ for the synthesis of hydrocarbons by the Fischer-Tropsch process can be improved in their capacity to form higher hydrocarbons, and their period of activity can be prolonged by reducing the metal carbonate (used in their preparation) in presence of residual alkali and removing the alkali after or during the reduction. In example (I) kieselguhr, is suspended in a solution containing pure salts of Ni and Th, preferably Ni(NO₂)₂ and Th(NO₃)₄., the quantities being such that the ratio by weight of Ni:ThO₂:kieselguhr in the final catalytic mass is 100:18:100. A solution of K₂CO₃ or Na₂CO₃ is then added to the mixture to precipitate the Ni and Th completely as their carbonates. The insoluble material is separated and washed with distilled H₂O until the washings have a pH of about 10. The material is then dried and heated at 400º in a current of H₂ to reduce the NiCO₂ to Ni, the Th being converted to ThO₂. The slight amount of alkali, necessary during reduction, is then removed by washing with distilled H₂O, while boiling, until the washings have pH of about 7. The mass is then dried by heating in a current of H₂. In example (II). The NiCO₃ and Th(CO₃)₂ are precipitated on kieselguhr, and the insoluble material is separated, washed, and dried, as in example (I): a powdered catalytic mass (0.5%-5.0% of the weight of the final catalytic mass) previously prepared and reduced as described in example (I), is added; the mixture is reduced by heating at 350º in a current of H₂: and the alkali is completely removed by washing and the mass dried as in example (I). This results in a further improved catalytic mass. For preparation of catalytic masses useful at higher temperature, the presence of Ce (1% of Ce₂O₂ based on combined weights of Ce₂O₃ and ThO₂) in the catalytic mass containing Ni and Th is beneficial. Substitution of (NH₄)₂CO₃ for K₂CO₃ or Na₂CO₃ above is permissible, and results in volatilization of the alkali during reduction.

CHEFFER, P. See abs. 348.

CHEMICAL CONSTRUCTION CORP. See abs. 2782.

CHEMICAL FOUNDATION, INC. See abs. 368.