2752. REED, H. C., AND BERG, C. H. O. (Union Oil Co. of California). Hydrogen. United States Patent 2,635,947, Apr. 21, 1953. Chem. Abs., vol. 47, 1953, p. 6637.

H is produced in a 4-stage process, which comprises: (1) Coking a hydrocarbon oil in the presence of fluidized particles of a higher oxide of Fe at 371°-649° to form a distillate and a deposit of coke on the particles; (2) separating the particles from the distillate and, while still in a fluidized state at about 538°-816°, treating them with a gas containing O₂ to burn the C and to heat and reduce the particles of Fe oxide with the formation of a gas containing CO and coke-free, reduced Fe-containing particles; (3) fluidizing the particles thus obtained in steam at 427°-816° to form H₂ and reform the higher oxide of Fe; and (4) separating the H₂ and recirculating the oxide to treat more oil. When the process is applied to a hydrocarbon fraction with a low A. P. I. gravity and containing S compounds, Fe sulfides are formed with desulfurization of the fraction. To prevent undue concentration of Fe sulfides in the catalyst, a side stream of catalyst is removed from the H₂ generator and is oxidized in an O₂ regenerator with the formation of SO₂ and higher Fe oxides, mostly Fe₂O₃ at temperature 538°-1,093°.