1815.  ------. [KEITH, P. C.] (Hydrocarbon Research, Inc.). Hydrocarbon Synthesis. United States Patent 2,631,159, Mar. 10, 1953; appl. filed Jan. 31, 1945, Serial No. 575,417; 7 claims (Cl. 260-449.6).

Synthesis gas is passed through a number of tubular reaction zones that become one at their upper and lower ends. Catalyst, such as powdered Fe, in fluidized condition fills the reaction zones as well as the merging zones. The tubular zones are surrounded with a coolant such as H₂O, Dowtherm, or Hg. It is important that the tubes have an internal radius of not less than ½ in. and not more than 2 in. The linear velocity should be 0.5-1.5 ft. per sec. In the merging zones the gas velocity may be as low as 0.03 ft. per sec. or lower. The entire reaction mass is maintained at 600º F. 1 literature ref. and 4 United States patents cited.