3851.  VOORHIES, A., AND KREBS, R. W. (Standard Oil Development Co.). Hydrocarbon Synthesis Plant. United States Patent 2,556,861, June 12, 1951; appl. filed Sept. 15, 1948, Serial No. 49,426; 7 claims (Cl. 260-449.6).

High yields of hydrocarbons, unaccompanied by excessive C formation and catalyst disintegration, are obtained by operating a plurality of fluid synthesis reactors in parallel, each reactor being charged with catalyst of different average age. The amount of feed gas and recycle tail gas to enter each reactor is adjusted to the age of the catalyst, so that maximum quantities of C4+ hydrocarbons and minimum C formation occurs. 4 United States patents cited.