2689.     ---------------.  [PICHLER, H., AND ZIESECKE, K. H.]  [High-Pressure Hydrogenation of Carbon Monoxide, Especially to Isoparaffin Hydrocarbons.  (Isosynthesis).  II.  Tests on Composite Catalysts and the Conversion of Dimethylether.]  Brennstoff-Chem., vol. 30, 1949, pp. 60-68, 81-84; TOM Reel 279, item 13, frames 789-931.

                    In the continual development of isosynthesis catalysts, a number of composite catalysts were subjected to thorough investigation.  It was found that by adding ZnO to ThO₂ the yield of liquid hydrocarbons was increased, and by adding Al₂O₃ the isobutane yield was increased.  The yield of isobutane was especially high when 3% K₂CO₃ was added to the aluminum precipitate of a ThO₂+20% Al₂O₃ catalyst.  At 300 atm. and 450°, the yield was about 85 gm. per N m.³ of pure gas, or 51% of the hydrocarbons produced.  When an alkali-free (ThO₂+20% Al₂O₃) catalyst was used at 600 atm. and 450°, 130 gm. of liquid hydrocarbons plus gasol per N m.³ of CO-H₂ mixture were obtained.  The yield consisted of 61 gm. of isobutane and 56 gm. of liquid hydrocarbons.  With the correct amount of ZnO:Al₂O₃, it was possible to replace some of the ThO₂.  However, the space-time yield was not obtained.  A 4-month, large-scale laboratory test with (ThO₂+20% Al₂O₃) catalyst demonstrated the long life and the regenerability of the isosynthesis catalyst.  Some investigation was made of the occurrence of dimethylether in the isosynthesis reaction, particularly with ThO₂.  It was found that considerable amounts of isobutane could be produced.