1223.    ---------------.  [GORDON, K.] Production of Petroleum by Synthetic Methods.  Gas World, vol. 127, 1947, p. 78; Chem. Age, vol. 57, 1947, pp. 221-222, 269-270.

        Paper presented at St. Andrew’s symposium.  Discusses 2 main methods for the production of gasoline – coal hydrogenation and Fischer-Tropsch synthesis.  Coal has been used at Billingham as the raw material; it has now been superseded by creosote oil and tar, as the coal caused great abrasion of the plant and during the war the plant could be more easily and safely shut down in case of air attack.  When coal is used, it is first washed by flotation, then powdered and mixed with oil to give a paste from which the oil may be recovered by recycling.  Owing to the nature of coal, about 5% avoids hydrogenation, a figure that may be increased if the coal is alkaline.  To obtain more complete hydrogenation it is customary to add to the charge a small excess of HCl in the form of NH₄Cl.  The ideal method of hydrogenating coal is to use 4 stages, although a satisfactory product may be obtained using 2, while at Billingham 3 stages are employed.  In the initial stages the catalysts employed are Sn oxide and Fe sulfide, and in the final stage WS₂.  The product from coal or tar hydrogenation is purely hydrocarbon in character in the fraction boiling up to 180°; above this temperature phenols and basic substances are obtained.  The average yield of gasoline from bituminous coal is about 50%, although this figure will be slightly increased if the gasoline is for motor fuel and decreased if for aviation fuel.  German annual output during the war was about 4,000,000 tons, while that at Billingham and Heysham was 500,000 tons.  Gasoline obtained by this method has an octane number of 80, which can be increased to 95 by addition of Pb, and to 100 by addition of iso-octane.  The economic prospects for this process are less favorable than they were 20 yr. ago mainly due to the increased costs of coal and labor, coupled with the fact that the gasoline sold today is of a higher quality than formerly.