PATENT

3510. ----- [STANDARD OIL CO.]  Hydrocarbons From Carbon Monoxide and Hydrogen.  British Patent 615,381, Jan. 5, 1949.  Chem. Abs., vol. 43, 1949,p. 4447.

Activity of a fluidized Fe or Co catalyst is maintained at a substantially constant level by the use of 2 or more   hydrogenation zones in series.  Fresh or regenerated catalyst of relatively high activity is fed to the last zone and passes successively by overflow devices through other hydrogenation zones to the 1st zone. in which it has relatively low activity, and is withdrawn.  H2 and CO are fed to the 1st zone and flow through the series of zones countercurrent to the flow of catalyst.  In each zone some conversion takes place.  The 1st zone is the largest and the zones become successively smaller so that the superficial and space velocities throughout the system remain approximately constant.  Gives flow diagrams.