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PATENTS 2839. RUBIN, L. C., AND MCGRATH, H. G. (M. W. Kellogg Co.). Synthesis of Organic Compounds. United States Patent 2,620,346, Dec. 2, 1952; appl. filed Sept. 24, 1948, Serial No. 50,966; 6 claims (Cl. 260-449.6). Finely divided catalyst is fluidized and heated to 350° F. or higher before contact with synthesis gas. The use of synthesis gas as the fluidizing gas in the starting-up procedure conveniently heats the catalyst mass to operating temperature. There should be < 15 parts by weight of CO per part by weight of the reduced catalyst. The heat is supplied by the exothermic reaction of H2 and CO. 4-6 lb. CO (using 2:1=H2: CO gas) is enough to raise each lb. catalyst mass from 300° to 360° F. The main purpose is to assure proper fluidization and to preheat the catalyst mass to operating temperature without excessive formation of wax upon the catalyst during startup. In main operating run, the temperature should be maintained >350° at all times. At 350°-450° F., space velocities of 50-2,000 vol. reactants per hr. per vol. of fluidized dense phase are satisfactory; higher velocities being associated with higher temperatures. For catalysts comprising about 1/3 by weight of hydrogenating metal, the above range corresponds to 0.2-81. per hr. per gm. of hydrogenating metal. Such operation gives maximum yield of liquid products and a minimum production of solids. The liquid product contains a valuable diesel fuel fraction. 5 United States patents cited. |