GB300264A - A process for the purification of sulphonic acids, naphthenic acids and the like - Google Patents

Abstract

300,264. Naamlooze Vennootschap de Bataafsche Petroleum Maatschappij. Nov. 11, 1927, [Convention date]. Mineral and tar oils, purifying.-Petroleum or other emulsions in which water forms the inner phase are broken by sulphonic or naphthenic acids or salts which have been purified by precipitation from their aqueous solutions by adding a volatile electrolyte such as hydrochloric, nitric, or acetic acid or ammonia, the impurities (inorganic salts &c.) remaining in the aqueous solution. The quantity of the precipitant required may bediminished by adding a liquid insoluble in water such as benzene or a mineral oil fraction, the volatile precipitant and the added liquid being removed from the purified acid by distillation; if desired, air or other gas may be passed through, or vacuum may be 'applied, or a suitable solvent such as a mineral oil may be added, to facilitate the distillation. In examples of the production of the de-emulsifying agents (1) mineral lubricating oil containing 1.5 per cent of naphthenic acid is treated with concentrated sulphuric acid, and after the removal of the acid sludge is neutralized with caustic soda solution; the aqueous layer is removed and treated with 50 per cent alcohol to extract the naphthenic acid soaps; the alcohol is distilled off and benzene and water are added, forming an emulsion; ammonia is added to flocculate the naphthenic acid soaps which are separated from the aqueous solution and freed from water, benzene, and ammonia by distillation. (2) The acid sludge formed by treating mineral lubricating oil with oleum is diluted with water, which causes the separation of the sulphonic acids and the like. These acids are dissolved in water and treated with hydrochloric acid to precipitate, the acids : after repeating the process the water and hydrochloric acid are removed by distillation.