2437.     NEUMANN, R. AND SCHROEDER, W. C.  Fischer-Tropsch Plant of Hoesch Benzin A.-G. at Dortmund, Germany.  FIAT Rept. 239, 1945, 5 pp.; PB 1279, TOM Rept. 22, TAC Rept. SnMC-8, TOM Reel 199.

        This plant employed the medium-pressure process using the normal Co-ThO₂-MgO-kieselguhr catalyst at about 10 atm. pressure and 180°-205° with synthesis gas of CO:H₂ ratio of 1:2 made from blue water gas.  The catalyst chamber house contained 68 converters of the usual concentric double-tube design.  They were operated in 3 stages:  1^st 40 chambers, 2d 16-20, and 3d 4-8.  Each stage was followed by indirect coolers and, following the final stage, gas pressure was reduced, and the C₃ and C₄ hydrocarbons were removed in the usual active C absorbers.  There were no facilities for recycling the gas through any stage.  The rate of feed of synthesis gas to the first stage was 1,000 m.³ per hr. per chamber.  The gas contraction was 50-60% for the 1^st stage, 35-40% for the 2d and 30% for the 3d.  The average yield of primary product was 150 gm. per m.³ of synthesis gas or a total production of 50,000 ton per yr.  The procedure of adding fresh catalyst in any stage instead of the 3d stage only differs from the usual practice as recommended by Ruhrchemie.  The regeneration of the catalyst with H₂ was claimed unsatisfactory and extraction with middle oil from the process was practiced instead.  The catalyst gave only 1,500-2,000 hr. service when it was removed and shipped back to Ruhrchemie as spent catalyst.  The products obtained from the primary product were approximately:  Benzine 20-25% with 40-45 octane no., Diesel oil 30% with 100 cetane no., heavy oil 25%, paraffin 20-25% with melting point of 60°-70° and an initial boiling point of approximately 350°.  Little research had ever been carried out at this plant.