3354.     ---------------.  [TECHNICAL OIL MISSION.]  [Middle-Pressure Synthesis With Iron Catalysts.]  Transl. of German documents on the Development of Iron Catalysts for the Fischer-Tropsch Synthesis.  Part II, 1946, pp. 21-24; TOM Reel 101, Doc. PG-21,578-NID.

        This summary was made some time after September 1940, when plans were being made to modify the equipment for use with the Fe catalyst at temperatures below 225° and pressure not above 10 atm.  Certain factors influencing the synthesis at lower temperatures are presented.  A very active catalyst must be used, such as can be obtained by precipitation from an Fe-salt solution, having added thereto a promoter such as 1% or less of Cu and about 0.25% of alkali.  Proper induction of the catalyst is required by using CO-rich gases at low pressures and a higher-than-synthesis temperature.  The synthesis temperature should be carried out at a maximum pressure of 8-10 atm. and with a H₂-rich synthesis gas.  Under such conditions, conversion takes place at lower temperatures.  For example, with a gas mixture of CO:H₂=1:10 conversion took place at 130°, and at 140°, it amounted to 38% with a gas contraction of 12%; with a ration of 1:4, the synthesis temperature varied between 180°-200°, therefore quite comparable to the conditions of the CO synthesis.  Fe catalysts produce reaction products that contain larger quantities of gasol and oxygenated organic compounds, than do Co catalysts.  Multistage operation or recycling is the most economical method; the higher the H₂ content of the gas, the more stages are recommended.