843.    ERDELY, A., AND NASH, A. W.  Catalysts Used in the Synthesis of Higher Hydrocarbons From Water Gas.  Jour. Soc. Chem. Ind., vol. 47, 1928, No. 32, pp. 219-223T; Chem. Abs., vol. 22, 1928, p. 3818.

     A continuation of Elvin’s experiments (abs. 816).  From the experiments with different unpromoted catalysts at 285°, and with a gas mixture containing equal parts of CO and H2, a Co-Cu-ZnO catalyst appears to be most suitable.  After the initial period, its activity was very constant, causing a contraction of about 50% for several days continuous operation.  A Co-Cu-Al2O3 catalyst gave nearly as satisfactory a performance, although less oil and more H2O was formed in its presence.  The oil yield was highest with an unpromoted Co-Cu catalyst, although the activity of this catalyst decreased more rapidly.  A Co-Cu-CeO2 catalyst gave the lowest yield of H2O and a fair yield of oil, but although the initial activity of this catalyst was the greatest, its activity decreased about as rapidly as that of the Co-Cu.  Catalysts supported on silica gel were as active as the Co-Cu-Mn catalyst only in 1 instance.  In this connection, the importance of the relative proportions of catalyst to support was shown.  The optimum temperature for the formation of liquid hydrocarbons was found to be 280°-290° for the Co-Cu-Al2O3 catalyst.  Above 290° CO2 and CH4 are the chief products, and below 230° no reaction was observed.  An excess of H2 in the initial gas mixture increased the H2O formation, while an excess of CO rapidly decreased the activity of the catalyst.  The gas velocity exerts a marked influence on the yield of products.  The optimum space velocity for the Co-Cu-ZnO catalyst was about 120 vol. of gas per hr. per unit vol. of catalyst.