Improvements in or relating to the manufacture of valuable oils and/or gases from coal by a hydrogenation process

摘要

Hydrocarbon oils and gases are obtained from coal by subjecting the coal to extraction with an organic solvent or solvent mixture, removing the solvent from the extracted fraction and replacing it by a second solvent capable of holding the extracted material in solution or suspension, and subjecting the composition so formed to hydrogenation. When a gaseous final product is desired, the hydrogenation product is subjected to thermal decomposition at temperatures between 700--900 DEG C. As first solvents, hydrocarbons or other neutral solvents may be used, e.g. tetrahydronaphthalene, decahydronaphthalene, or hydrocarbons boiling above 250 DEG C., e.g. phenanthrene, hydrogenated phenanthrenes and anthracenes, benzylnaphthalenes, diphenylbenzene and tetra-amylene; or phenols, e.g. tar acids, p p-benzyl-phenol, or 1-(a -hydroxy-benzyl) naphthalene; or basic compounds, e.g. pyridine, quinoline, quinaldine, acridine, benzyl quinolines, hydrogenated acridines and other hydrogenated heterocyclic bases. Preferably, a neutral solvent is used with a phenol or basic solvent. Extraction temperatures of 200--400 DEG C. are employed, the temperature being raised in stages. As second solvent, a cheap substance not substantially altered in the hydrogenation stage is preferred, e.g. mixtures of hydrocarbon oils produced by the hydrogenation of coal extracts, low temperature tars or tetradecahydroanthracene, tetradecahydrophenanthrene, tricyclohexyl or dicyclohexylmethane, tricyclo or dicyclohexyl ethane or dodecahydrodiphenyl. The second solvent is added after the first has been removed by distillation or when the second solvent has a higher boiling point it may be added direct to the extract and the first solvent then distilled off. The extract is then mixed with a solution or suspension of a catalyst, e.g. nickel, molybdic acid, phosphoric acid, ammonium molybdate, tungstate, or phosphate, tin oxalate or hydroxide. The molybdenum catalysts are preferably heated in air to 500 DEG C. before use. The hydrogenation is carried out at 200--600 DEG C. and preferably under low pressure due to that produced by a small amount of hydrogen and the vapour pressure of the solvent. The oils obtained may be used as fuel oils or may be subjected to further hydrogenation to produce lighter oils. The oils are converted into olefines by heating their vapours in a turbulent stream to 700--900 DEG C. while at temperatures above 1000 DEG C. acetylene is obtained. The olefines may be recovered by absorption in charcoal or sulphuric acid. Powdered bituminous coal is extracted under a pressure of 50--70 atmos. with a mixture comprising 85 parts hydrogenated naphthalene and 15 parts quinoline, the temperature being raised at intervals from 260--350 DEG C. The solution is separated from the residue and after desulphurization with alkali is mixed with an oil of boiling range 290--380 DEG C., obtained by hydrogenation, and a previously heated molybdenum catalyst. The first solvent is separated by distillation and the remaining mixture hydrogenated at 450--500 DEG C. under 80 atmos. pressure. The oils produced are again hydrogenated under similar conditions and the products are vaporized and led through narrow tubes heated to 900 DEG C. A gas is obtained containing considerable proportions of olefines particularly ethylene and propylene.ALSO:Hydrocarbon oils and gases are obtained from coal by subjecting the coal to extraction with an organic solvent or solvent mixture, removing the solvent from the extracted fraction and replacing it by a second solvent capable of holding the extracted material in solution or suspension, and subjecting the composition so formed to hydrogenation. When a gaseous final product is desired the hydrogenation product is subjected to thermal decomposition at temperatures between 700--900 DEG C. As first solvents hydrocarbons or other neutral solvents may be used, e.g. tetrahydronaphthalene, decahydronaphthalene, or hydrocarbons boiling above 250 DEG C., e.g. phenanthrene, hydrogenated phenanthrenes and anthracenes, benzylnaphthalenes, diphenyl-benzene and tetraamylene; or phenols e.g. tar acids, p-benzylphenol, or 1-(b -hydroxy-benzyl) naphthalene; or basic compounds e.g. pyridine, quinoline, quinaldine, acridine, benzyl quinolines, hydrogenated acridines and other hydrogenated heterocyclic bases. Preferably a neutral solvent is used with a phenol or basic solvent. Extraction temperatures of 200--400 DEG C. are employed the temperature being raised in stages. As second solvent a cheap substance not substantially altered in the hydrogenation stage is preferred, e.g. mixtures of hydrocarbon oils produced by hydrogenation of a coal extract, low temperature tars or tetradecahydroanthracene, tetradecahydrophenanthrene, tri- or dicyclohexylmethane, tri- or di-cyclohexyl ethane or dodecahydrodiphenyl. The second solvent is added after the first has been removed by distillation or when the second solvent has a higher boiling point it may be added direct to the extract and the first solvent then distilled off. The extract is then mixed with a solution or suspension of a catalyst e.g. nickel, molybdic acid, phosphoric acid, ammonium molybdate, tungstate or phosphate, tin oxalate or hydroxide. The molybdenum catalysts are preferably heated in air to 500 DEG C. before use. The hydrogenation is carried out at 200--600 DEG C. and preferably under low pressure due to that produced by a small amount of hydrogen and the vapour pressure of the solvent. The oils obtained may be used as fuel oils or may be subjected to further hydrogenation to produce lighter oils. The oils are converted into olefines by heating their vapours in a turbulent stream to 700--900 DEG C. while at temperatures above 1000 DEG C. acetylene is obtained. The olefines may be recovered by absorption in charcoal or sulphuric acid. Powdered bituminous coal is extracted under a pressure of 50--70 atmos. with a mixture comprising 85 parts hydrogenated naphthalene and 15 parts quinoline the temperature being raised at intervals from 260--350 DEG C. The solution is separated from the residue and is mixed with an oil of boiling range 290--380 DEG C. obtained by hydrogenation and a previously heated molybdenum catalyst. The first solvent is separated by distillation and the remaining mixture hydrogenated at 450--500 C. under 80 atmos. pressure. The oils produced are again hydrogenated under similar conditions and the products are vaporized and led through narrow tubes heated to 900 DEG C. A gas is obtained containing considerable proportions of olefines particularly ethylene and propylene. According to the second Provisional Specification decalin, tetralin, dihydroanthracene, ketones, and organic bases boiling above 250 DEG C. may also be used as solvents to extract the coal.