PATENT

3487. ----- [STANDARD OIL CO.]  Fischer-Tropsch Catalyst.  British Patent 596,162, Dec. 30, 1947; appl.  filed July 23, 1945.  Chem. Abs., vol. 42, 1948, p. 3933.

Spherical particles of SiO₂ hydrogel are prepared by formed when separate solutions of Na silicate and H₂SO₄, HNO₃, or HCL are mixed by means of a jet.  The mixture is subsequently emulsified by a 2d jet as the dispersed phase in 2-20 times its vol. of a wholly or partly immiscible substance, such as BuOH, ethers, naphtha, or light gas oil, at room temperature to 250° F. and atmospheric pressure to 50 p. s .i.  H₂O is added after the sol is set to a hydrogel (1-60 min.), and the H2O-gel mixture is separated.  The gel is washed and impregnated with aqueous solutions of the nitrates of Co and Th in such proportions that the fluidized mass contains 15-40% Co and 2-10% Th.  The impregnated gel is dried at 212° Fl. to reduce the H2O content to 6-10% and then is heated 4 hr. at 420° f. to decompose the nitrates to the corresponding oxides.  The dried gel is formed into 1/8 in. pills and the Co oxide reduced to Co with H₂ for 4 hr. at 650°-700° F., with use of space velocities of 4,000-6,000 vol. per vol. of catalyst per hr.  After reduction, apparent d. 56.1 lb. per cu. ft., the pills are ground to powder containing less than 25%, having particle size 0-20 micron diam. and having apparent density in the fluidized state of 10-35 lb. per cu. ft.  Carbonates of Co and Th may be precipitated on the gel in place of nitrates.  Mg, U, Mn, or Al nitrates, acetates or chlorides may replace Th.  Catalysts thus prepared have improved resistance to attrition, contain less friable matter, and are retained better on the carrier.  They are suitable in either fluidized or bed-type operations.  Gives an example in which the Co-Th oxide catalyst is used to reduce CO at 390°-400° F. to liquid hydrocarbons.