438.    CARR, T. P.  Coke Oven Managers’ Association, Midland Section.  Inaugural Address.  Gas World, vol. 109, No. 2835, Coking Section 12-14, 1938; Chem. Abs., vol. 33, 1939, p. 1124.

                   Review of developments in the coking industry during the past few years.  Process depends for its action on conversion of coke into water gas.  The water gas is divided into 2 portions:  1 portion is specially treated in a gas-cracking apparatus, and the cracked gas is then reblended with the remaining portion of the water gas.  The net result of this mixture is to give a gas consisting of approximately 30 parts by volume of CO and 60 parts by volume of H₂.  The synthesis gas so produced is then passed over a catalyst consisting of a Co-Th preparation deposited on kieselguhr at atmospheric pressure and at a temperature of approximately 220° C. a mixture of oils is produced, which can be fractionated into gasol, petrol, diesel oil, and paraffin wax.  The gasol consists mainly of propane and butane, which can be sold for country-house lighting and heating and is very similar to the Calor gas marketed in England.  The diesel oil is of particularly high quality, having a cetane value of 100, while the petrol is of rather low octane value as compared with the spirit obtained from the hydrogenation process.  This petrol can, however, be improved by cracking, and further improvements can be obtained by cracking the diesel oil and paraffin wax produced and blending these cracked products with the petrol.  At present the motor-fuel production from this process in Germany is at the rate of approximately 600,000 tons per yr., while there is 1 unit in operation in France producing motor fuel at the rate of 13,000 tons per yr.  It is impossible to give a detailed list of the various plants operating on the continent, but the above figures of output can be taken as being substantially correct.  The actual proportion of coal or coke used for producing 1 ton of motor spirit naturally varies according to the process adopted, since the Fischer-Tropsch process can operate in a number of different ways.  For example; coking coal may be converted into coke, which, in turn, is converted into water gas, as already indicated.  Lignites or brown coals may be gasified in special producers to give synthesis gas direct without any intermediate coking, materials of the nature of cannel or oil shale may be carbonized, the gas being used for the conversion into synthesis gas and the coke being used for providing the necessary heat for the generation of steam and power for the process, and the large yield of tar from such carbonization being cracked to give high-octane-value spirit.  With the conversion of coal into coke, the amount of coal required to produce 1 ton of primary products may be approximately 5 tons, whereas, with the use of cannels or similar materials, the quantity of coal used may only amount to 2 ½ tons per ton of spirit produced.