Patent GB-482431-A (GB)
Title: Improvements in the manufacture and production of aromatic hydrocarbons, in particular benzene and toluene, from mineral coals by destructive hydrogenation
IPC: C10G47/00
Filed: 1937-11-04
Abstract: High yields of aromatic hydrocarbons of low boiling point, e.g benzene and toluene, are obtained by separating a middle-oil fraction boiling from 180-325 DEG  C., produced by the destructive hydrogenation of carbonaceous materials, into two fractions of boiling range 275-375 DEG  C. and 180-275 DEG  C. respectively, freeing the fraction of lower - boiling range from phenol, and then subjecting it to an aromatizing destructive hydrogenation by leading it in the form of vapour with hydrogen at above 500 DEG  C., and under 50-200 atmos. pressure over catalysts, e.g. oxides of the metals of Group 6, the aromatic hydrocarbons of low boiling point being recovered from the product by distillation.  The higher-boiling fraction, preferably together with the phenol separated from the lower boiling fraction, is hydrogenated in the vapour phase at temperatures below 490 DEG  C. and under a pressure of 250 atmos. in the presence of metal sulphides as catalysts, a saturated benzine boiling up to 200 DEG  C. being obtained which is further hydrogenated at 450-500 DEG  C. and under a maximum partial pressure of benzine vapours of 0,5 to 3 atmos. and a hydrogen pressure of 30-100 atmos. in presence of catalysts comprising sulphides or oxides of metals of Groups 5 and 6 together with sulphides or oxides of Groups 1-8.  An aromatic product is obtained from which benzene &c. are separated while the products of higher boiling point are further treated at temperatures above 500 DEG  C.  The coal thus treated is converted to the extent of 12 per cent into benzene and toluene.  In an example, finely ground Ruhr mineral coal impregnated with a tin oxalate solution and pasted with heavy oil obtained from the same coal by destructive hydrogenation, is destructively hydrogenated at 460 DEG  C. and 250 atmos.  The benzine and middle oil obtained are separated by distillation into fractions comprising (a) benzine, (b) middle oil boiling from 275-375 DEG  C., (c) middle oil boiling from 200-275 DEG  C.  The last fraction is separated from phenol and further treated by passage with hydrogen through a preliminary reaction vessel heated to 250 DEG  C. and filled with tungsten disulphide, a gas-heated preheater heated to 580 DEG  C. and a reaction vessel filled with a mixture of molybdic acid and zinc oxide, the throughput being 2 kgs. of middle oil per litre catalyst volume per hour. 333 kgs. benzine are obtained containing 23 kgs. benzene, 50 kgs. toluene, and 53 kgs. xylene.  The 275-325 DEG  C. fraction, with the phenols separated from the other fraction, is treated at 425 DEG  C. and 200 atmos. pressure in presence of tungsten disulphide, the throughput being 0,8 kgs. per litre of catalyst volume per hour.  The 70-170 DEG  C. fraction of the benzine thus produced is mixed with the benzine obtained in the hydrogenation of the coal and the mixture is hydrogenated at 495 DEG  C. and 50 atmos. in presence of a mixture of tungsten and nickel sulphides, 466 kgs. of benzine being obtained from which, by extraction by means of propane and sulphur dioxide, 19 kgs. benzene, 40 kgs. toluene and 38 kgs. xylene are separated from the higher aromatic hydrocarbons; the latter are retreated at 580 DEG  C. and 200 atmos. in presence of molybdenum and zinc oxides.ALSO:High yields of aromatic hydrocarbons of low boiling point, e.g benzene and toluene, are obtained by separating a middle oil fraction boiling from 180-325 DEG  C. produced by destructive hydrogenation of carbonaceous materials into two fractions of boiling range 275-375 DEG  C. and 180-275 DEG  C. respectively, freeing the fraction of lower boiling range from phenol and then subjecting it to an aromatizing destructive hydrogenation by leading it in the form of vapour with hydrogen at above 500 DEG  C. and under 50-200 atmos. pressure over catalysts, e.g. oxides of the metals of Group 6, the aromatic hydrocarbons being recovered from the products by distillation.  The higher-boiling fraction, preferably together with the phenol separated from the lower - boiling fraction is hydrogenated in the vapour phase at temperatures below 490 DEG  C. and under a pressure of 250 atmos. in the presence of metal sulphides as catalysts, a saturated benzine p  boiling up to 200 DEG  C. being obtained, which is further hydrogenated at 450-500 DEG  C., and under a partial pressure of benzine vapours of 0,5 to 3 atmos. and a hydrogen pressure of 30-100 atmos. in presence of catalysts comprising sulphides or oxides of metals of Groups 5 and 6 together with sulphides or oxides of Groups 1-8.  An aromatic product is obtained from which benzene &c. are separated while the products of higher boiling point are further treated at temperatures above 500 DEG  C.  The coal thus treated is converted to the extent of 12 per cent into benzene and toluene.  In an example finely ground Ruhr mineral coal impregnated with a tin oxalate solution and pasted with heavy oil obtained from the same coal by destructive hydrogenation, is destructively hydrogenated at 460 DEG  C. and 250 atmos.  The benzine and middle oil obtained are separated by distillation into fractions comprising (a) benzine, (b) middle oil boiling from 275-325 DEG  C., (c) middle oil boiling from 200-275 DEG  C.  The last fraction is separated from phenol and further treated by passage with hydrogen through a preliminary reaction vessel heated to 250 DEG  C. and filled with tungsten disulphide, a gas-heated preheater heated to 580 DEG  C., and a reaction vessel filled with a mixture of molybdic acid and zinc oxide, the throughput being 2 kgs. of middle oil per litre catalyst volume per hour; 333 kgs. benzine are obtained containing 23 kgs. benzene, 50 kgs. toluene, and 53 kgs. xylene.  The 275-325 DEG  C. fraction, with the phenols separated from the other fraction, is treated at 425 DEG  C. and 200 atmos. pressure in presence of tungsten disulphide the throughput being 0,8 kgs. per litre of catalyst volume per hour.  The 70-170 DEG  C. fraction of the benzine thus produced is mixed with the benzine obtained in the hydrogenation of the coal and the mixture is hydrogenated at 495 DEG C. and 50 atmos. in presence of a mixture of tungsten and nickel sulphides, 466 kgs. of benzine being obtained, from which by extraction by means of propane and sulphur dioxide 19 kgs. benzene, 40 kgs. toluene and 38 kgs. xylene are separated from higher aromatic hydrocarbons which are retreated at 580 DEG  C. and 200 atmos. in presence of molybdenum and zinc oxides.