Patent GB-499978-A (GB)
Title: A process for removing weakly acid-reacting organic compounds from liquids chiefly consisting of liquid mixtures of hydrocarbons or hydrocarbon derivatives
IPC: C10G29/28
Filed: 1937-09-08
Abstract: Liquid hydrocarbons and their nitrogen and halogen derivatives are freed from weakly acidic organic compounds by extraction with a ternary sulphonium base <FORM:0499978/III/1> dissolved in water or a non-acidic organic solvent miscible with water but not with the liquid treated.  A strong inorganic base, e.g. alkali hydroxide may be present; and if the liquid treated contain strongly acid-reacting substances, e.g. hydrogen sulphide or carboxylic acid, it may first be treated with alkali hydroxide or the like.  Specified treatments are the removal of mercaptans, phenols, naphthenic acids, and fatty acids from petroleum hydrocarbons, benzene, toluene, xylene, chlorethane, dichlor-ethylene, trichlor-ethylene, carbon tetrachloride, chlor-propane, chlor-butylene, chlorbenzene, brom-benzene, nitro-ethane, nitrobenzene, amylamines, aniline, pyridine, and petroleum bases.  Organic solvents suitable are lower alcohols, ketones, amines, quaternary ammonium bases, amino-alcohols, and alcohol halides.  Ternary sulphonium bases specified are methyl- and benzyl - diethyl sulphonium hydroxides, and those in which the radicles R1, R2, R3 are alkyl, unsaturated alkyl, aryl, or aralkyl-which may contain polar groups, e.g. -OH, -NH2, -NO2, or halogens-or are heterocyclic radicles.  The bases may be produced by adding an alkyl iodide or other halide to an organic sulphide R1-S-R2, e.g. methyl a -pyridyl sulphide NC5H4-S-CH3 or 2-mercapto-thiophene <FORM:0499978/III/2> and replacing the halogen in the resulting sulphonium halide by hydroxyl.  Dimethyl (b a  - oxido - propyl) sulphonium hydroxide <FORM:0499978/III/3> in such a product.ALSO:Liquid hydrocarbons and their nitrogen and halogen derivatives are freed from weakly acidic organic compounds by extraction with a ternary sulphonium base <FORM:0499978/IV/1> dissolved in water or a non-acidic organic solvent miscible with water but not with the liquid treated.  A strong inorganic base, e.g. alkali hydroxide may be present; and if the liquid treated contain strongly acid-reacting substances, e.g. hydrogen sulphide or carboxylic acid, it may first be treated with alkali hydroxide or the like.  Specified treatments are the removal of mercaptans, phenols, naphthenic acids and fatty acids from petroleum hydrocarbons, benzene, toluene, xylene, chlorethane, dichlorethylene, trichlorethylene, carbon tetrachloride, chlorpropane, chlorbutylene, chlorbenzene, brom-benzene, nitroethane, nitrobenzene, amylamines, aniline, pyridine, and petroleum bases.  Organic solvents suitable are lower alcohols, ketones, amines, quaternary ammonium bases, amino-alcohols, and alcohol halides.  Ternary sulphonium bases specified are methyl- and benzyl - diethyl sulphonium hydroxides, and those in which the radicles R1, R2, R3 are alkyl, unsaturated alkyl, aryl, or aralkyl-which may contain polar groups, e.g. -OH, -NH2, -NO2, or halogens-or are heterocyclic radicles.  The bases may be produced by adding an alkyl iodide or other halide to an organic sulphide R1-S-R2, e.g. methyl a -pyridyl sulphide NC5H4-S-CH3 or 2-mercapto-thiophene <FORM:0499978/IV/2> and replacing the halogen in the resulting sulphonium halide by hydroxyl.  Dimethyl (b a -oxido-propyl) sulphonium hydroxide <FORM:0499978/IV/3> is such a product.