2101. ------. [MAIN, T. C.] (Standard Oil Development Co.). Hydrocarbon Synthesis. United States Patent 2,459,444, Jan. 18, 1949; appl. filed Nov. 8, 1946. Serial No. 708,626; 8 claims (Cl. 260-449.6). Chem. Abs., vol. 43, 1949, p. 3832.

Good fluidization of the Fe catalyst in Fischer-Tropsch synthesis is obtained by mixing with it an inert solid, such as silica gel, dolomite, sharp sand, or alumina ground to a relatively coarse particle size as compared to the Fe powder. A material balance on the 0-20-μ fraction indicates that 500 lb. of Fe powder should be diluted with 725 lb. of silica gel of particle size, giving a final mixture 25% 0-20-μ particles, 25% 0-20 and 25% 80+ fractions give excellent fluidization. The inert has less particle density than the Fe-C mixture. From the density standpoint, the Fe tends to concentrate in the lower region of the dense phase, the lighter inert powder in the upper regions, but from the standpoint of particle size, the fine Fe tends to move upwardly through the dense phase to the interface, and the course inert tends to move toward the bottom. These opposing effects tend to counterbalance one another, and good internal mixing results. Diluent does not retard catalyst activity. 3 United States patents cited.