Patent GB-156123-A (GB)
Title: Process for extraction of unsaturated hydrocarbons from hydrocarbon mixtures or carbonaceous material
IPC: C10G1/04
Filed: 1920-12-30
Abstract: A mixture of sulphur dioxide and a ketone, such as acetone, is used for the extraction at ordinary temperatures of hydrocarbons from carbonaceous substances and their distillation products, and for the separation of butadienes from other hydrocarbons.  The extraction may take place under pressure.  According to examples:-(1) acetone is saturated with sulphur dioxide and allowed to remain at atmospheric temperature and pressure in contact with pieces of hard coal; by steam distillation of the reddish liquid produced, a yellow oily hydrocarbon is obtained. Increasing the pressure gives a larger yield of the product; an apparatus is described in this connection.  (2) The extraction of lignite or bituminous brown coal with the acetone-sulphur dioxide mixture yields a resinous wax-like substance, which apparently results from the action of the sulphur dioxide on the lignite and the solution in the acetone of the product.  The lignite may previously be treated under pressure with alcoholic or aqueous caustic alkali and the residue after evaporation used for the acetone-sulphur dioxide treatment.  (3) Crude naphtha, when extracted with the acetone-sulphur dioxide mixture, separates into two layers, the clearer of which, after evaporation of the acetone and sulphur dioxide, yields unsaturated aromatic hydrocarbons; the saturated hydrocarbons remain in the other layer, being undissolved by the acetone-sulphur dioxide mixture.  (4) The acetone-sulphur dioxide mixture is used for absorbing diolefines from a mixture with other hydrocarbons.ALSO:A mixture of sulphur dioxide and a ketone, such as acetone, is used for the extraction at ordinary temperatures of hydrocarbons from carbonaceous materials such as coal and for the separation of unsaturated hydrocarbons from the distillation products of coal &c.  Other ketones which may be employed are methyl ethyl ketone, diethyl ketone, methyl propyl ketone, and ethyl propyl ketone. The extraction may take place under pressure.  According to examples:-(1) Acetone is saturated with sulphur dioxide and allowed to remain at atmospheric temperature and pressure in contact with pieces of hard coal; by steam distillation of the reddish liquid produced, a yellow oily hydrocarbon is obtained. Increasing the pressure gives a larger yield of the product; an apparatus is described in this connection.  (2) The extraction of lignite or bituminous brown coal with the acetone-sulphur dioxide mixture yields a resinous wax-like substance, which apparently results from the action of the sulphur dioxide on the lignite and the solution in the acetone of the product.  The lignite may previously be treated under pressure with alcoholic or aqueous caustic alkali and the residue after evaporation used for the acetone-sulphur dioxide treatment. (3) Crude naphtha, when extracted with the acetone-sulphur dioxide mixture, separates into two layers, the clearer of which, after evaporation of the acetone and sulphur dioxide, yields unsaturated hydrocarbons; the saturated hydrocarbons remain in the other layer, being undissolved by the acetone-sulphur dioxide mixture.