1011.    ---------------.  [Synthesis of Paraffin From Carbon Monoxide and Hydrogen Upon Cobalt Catalysts, Medium-Pressure Synthesis.]  Brennstoff-Chem., vol. 20, 1939, pp. 41-48; Chem. Abs., vol. 33, 1939, p. 9605.

        Laboratory- and semitechnical-scale apparatus is shown schematically and described.  The influence of various factors upon the process has been determined.  The 1:2 CO-H₂ mixture passed over Co-Th catalyst precipitated on kieselguhr at 185°-190° at the rate of 1 l./hr./gm. Co at pressures to 150 atm. gave maximum yields of solid and liquid hydrocarbons at 5 and 15 atm. in test runs over 4 weeks.  White solid products were obtained up to 50 atm.; at 150 atm. O-compounds were found together with Co carbonyl.  Maximum paraffin formed at 15 atm. in 70 gm./m.³ yield; oil boiling above 200° increased to a maximum at 5 atm.; maximum gasoline boiling to 200° was obtained at 1.5 atm.  Catalyst stability has been determined; its comparatively longer life at 5-15 atm. is outstanding.  Reaction temperature is controlled to give maximum conversion and increases up to 190°-195° at 5-15 atm. after 6 months.  Increasing pressure to increase throughput reduces conversion.  Repeated passage increases conversion.  A catalyst containing Cu gives poorer conversion as does the substitution of U for Th.  Alkalinization increased yields only at atmospheric pressure.  Experiments using 18, 6, 2, and 0% Th show that (1) paraffin is formed in lower yield without Th, (2) the reaction temperatures increase rapidly with lower Th content, and (3) gaseous products increase at the cost of the solid and liquid.  Co-Ni upon alloy skeleton improves yields at higher pressures, but these are lower than those with the precipitated catalysts and decrease with time more rapidly.  Almost entirely liquid yields are formed and Ni carbonyl is found beginning at 170° when precipitated Ni is used at medium pressures.  Under optimum conditions, 50% of the reaction products are paraffins that, freed of oil, melt at 80°-115°.  By extraction, fractions melting at 130° may be obtained from them.  Fractions boiling 300°-450° indicate products C₁₇H₃₆ to C₂₈H₅₈.  The use of medium pressure increases the fraction boiling above 300°; at 5-20 atm. 13-25% boils above 450°.  Of the 30°-300° fraction, half may be considered gasoline and half as diesel oil.  Products are water-clear and contain less unsaturated compounds than the usual pressure-synthesis products, these decreasing with increasing molecular weight.  Uses possible because of the high melting point of the paraffin are discussed.