3527.     UNITED STATES NAVAL TECHNICAL MISSION IN EUROPE.  Thoria-Alumina Catalyst for Isoparaffin Synthesis.  Tech. Rept., 110-45, 1945, 8 pp.; Oil Gas Jour., vol. 44, No. 37, 1946, pp. 86, 89; CIOS Rept., XXV-27; PB 289, 890.

        Digest of the report, Wartime Research on Synthetic Fuels by the Kaiser Wilhelm Institut für Kohlenforschung.  A catalyst of ThO2-Al2O3 (1:4) gives the best yields of all catalysts investigated.  Higher gas velocities may be used, the tendency for alcohol formation is low but high for C deposition.  Increasing the Al2O3 content increases CH4 formation, and addition of 0.5-1% K2CO3 raises the yield slightly.  ZnO-Al2O3 catalyst shows slightly lower yields but better commercial prospects.  Both catalysts are prepared by precipitation from the respective nitrate solution by means of Na2CO3.  For synthesizing isoparaffins, pressure of 300 atm. and temperatures of 420°-450° are best.  Yield drops rapidly below 300 atm., but, as pressures increase above this, the % of O-containing products increases until at 1,000 atm. the entire product is dimethyl ether.  Temperatures below 450° show increases of alcohol and unsaturates and a decrease in C deposition.  Above 450°, the reaction rate increases rapidly with mainly naphthenic products and excessive C deposition.  The best synthesis gas is CO:H2=1.2:1 and the best gas velocity 10 l. per hr. per 20 cc. of catalyst.  Operating with a ZnO-Al2O3 catalyst (1:4) with a CO:H2 ratio of 1 at 300 atm. and 450°, the yields per m.3 of gas were:  Total yield C3 and higher 120-130 gm.; C4 (90% isobutane) 50-80 gm., C5+(97% iso-) 30-60 gm.