PATENT

3249.----- .  [SCHARMANN, W. G. ]  (Standard Oil Development Co.).  Synthesis of Hydrocarbons. United States Patent 2,463,912, Mar. 8, 1949, appl.  filed Dec. 12, 1946, Serial No. 715,798; 15 claims (Cl. 260-449).  Chem. Abs., vol. 43, 1949, p. 4447.

Reacting gases are passed upwardly in series through 2 or more reactors with conventional means for heat control.  The velocities are adapted to establish dilute catalyst phases at the prevailing particle size and to carry the catalyst upward through the successive reactors into the final dense phase reactor from which the catalyst is recycled.  Product gas may be recycled to any or all of the various stages to control the desired flow velocities and/or partial pressures of the constituents of the gas phases.  Gas velocities of 1-20ft. per sec. at particle size 5-150 μ are suitable to establish dilute phase densities of 0.5—10 lb. per cu. ft. at space velocities of 2,000-20,000 vol. per vol. per hr. of fresh CO and H₂.  The dense phase reactor is preferably operated at low gas velocities of 0.1-3 ft. per sec. to obtain bed densities of 20-150 lb per cu. ft. at reduced space velocities of 5,000 vol. per vol. per hr. of fresh CO and H₂.  The desired differences in the superficial gas velocities within the individual reactors may be established by proper choice of reactor diameters in combination with proper gas recycle ratio.  The deposition of C on the Fe catalyst is thus substantially reduced.  2 United States Patents cited.