3734. TECHNICAL OIL MISSION. [Process for the Production of Hydrocarbons.] German Patent Appl. --, no date. TOM Reel 101, Doc. PG-21,576-NID; Transl. of German Documents on the Development of Iron Catalysts for the Fischer-Tropsch Synthesis, Part II, 1946, pp.6-10.

This invention describes a procedure that is said to overcome previous difficulties connected with the use of Fe catalysts and makes possible the replacement of the Co catalyst without diminishing the hydrocarbon yields or shortening the lifetime of the catalyst. This development consists in pretreating the Fe catalyst with pure CO or CO-rich gases at a pressure of about 0.1 atm., a maximum temperature of 320° -340° , and a contact time of about 24 hr. H₂ should not be present. It is believed that the improvement in catalyst activity is due to the formation of Fe carbides and the dispersion of a well-defined pattern of C throughout the crystal lattice. After induction, the preferable synthesis procedure is to use a synthesis-gas mixture of composition 1.5-2CO+1H₂ at a pressure of 10-30 atm. and a temperature of 200° -320° . Example: An Fe catalyst, precipitated from the nitrates and containing 0.1% of alkali, was inducted at 0.1 atm. for 24 hr. at 325° , with 4 l. CO per 10gm. Fe. Then the catalyst was operated with a synthesis gas consisting of CO+H₂ in the ration of 1.8:1 at a pressure of 15 atm. and a temperature of 235° . The gas contraction was 55%, corresponding to a complete conversion of the CO. The yields of solid, liquid, and gasol hydrocarbons were approximately 150 gm. per N m.³ of synthesis gas. The activity of the catalyst was still constant at the same operating temperature after 3 mo. The liquid hydrocarbons consisted chiefly of relatively antiknock benzine boiling up to 180° . 20 to 30 gm. of the total yield were C₃ and C₄ hydrocarbons partly unsaturated.