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1656. ---------------. [KAISER WILHELM INSTITUT FÜR KOHLENFORSCHUNG.] [Direct Synthesis of Isoparaffins From CO and H2.] TOM Reel 134, Item IV-3, December 1942; TOM Reel 259, Item 20, frames 1055-1071.
It was discovered that catalysts based on Th are particularly well suited for the synthesis of branched hydrocarbons from CO and H2. The best Th catalysts are produced by precipitation of Th salt solutions, generally by precipitation of the basic carbonate by Na2CO3 from the nitrate solutions. The lifetime of the Th catalyst is very long under the conditions of isosynthesis and can easily be regenerated. A water gas of CO:H2 ratio of 1:1-1.2:1 is used for the synthesis. The type of reaction products obtained is dependent on certain conditions such as composition and method of production of the catalyst, the temperature and pressure, the residence time of the gas in the catalyst space, operation in 1 or more stages, the material of the reaction tubes, etc. With a pressure of 150 atm. and a flow rate of the gases corresponding to 10 l. final gas per hr. per 28 gm. catalyst, the amount of alcohol and other O2-containing compounds, which prevail below 375°, decreases rapidly with rising temperature. Mostly liquid branched aliphatic hydrocarbons are formed, 375°-425°. With rising temperature, the amount of naphthenes gradually increases, reaching 50% at 450°-460°. Between 450° and 500° aromatics are identified. The amount of gaseous products increases from less than 10% at 375° to 50% at 440°, with isobutane the highest, and at 450°-460° 1/3 of the total products consists of this hydrocarbon. Unbranched aliphatic hydrocarbons appear in only very small amounts. N-butane results in amounts of about 10% of the isobutane. With a constant temperature of 450°, the reaction begins at 6 atm. pressure and at 30 atm. a 22% conversion of the CO takes place with a production of 5.1 gm. C3+n-C4, 5.4 gm. iso-C4 and 16.1 gm. liquid hydrocarbons/N-m.3 entering gas. The amount of products from a single operation increases with rising pressure, reaching at 500 atm. 46.5 gm. iso-C4 and 40.5 gm. gasoline plus oil. The yield of liquid hydrocarbons was greater than V2A stainless-steel pipes than with Cu pipes. The conversion of CO increases with rising pressure in a single operation, likewise at 50-100 atm., providing several operations instead of 1 are performed. Graphical and tabular data show the influence of temperature and pressure on the type and yield of products, as well as their distillation range and the composition of the various fractions. The composition of the reaction products can be varied within rather wide limits by choosing the synthesis conditions. The gasoline obtained at 450° and 150 atm. and hydrogenated had an octane number, after adding 0.08 vol. % of Pb, of 95; at 370° and 150 atm. 89.6%.
KALLENBERG, S. See abs. 2336.
KALLENBERGER, R. H. See abs. 576.