GB528904A - A process for removing organic acids from water-insoluble organic liquids - Google Patents

Abstract

528,904. Purifying liquid hydrocarbons, halogenated hydrocarbons, and organic bases. FIFE, J. G. (Naamlooze Vennootschap de Bataafsche Petroleum Maatschappij). March 30, 1939, No. 10008. Drawings to Specification. [Class 91] [Also in Group IV] Mercaptans, alkyl phenols, thiophenols, and other weakly acidic impurities are removed from such water-insoluble neutral or basic organic liquids as gasolene, kerosene, pentane, hexane, benzene, toluene, xylene, carbon tetrachloride, dichlorethylene, chlorpropane, and nitrogen bases, e.g. alkylated pyridines by extraction with an aqueous solution of a strong base in which is dissolved a substantial amount of at least two solubility promoters for the acidic impurities, one promoter being a phenolic-hydroxy-aromatic compound having oxidation-inhibiting properties and the other an aliphatic or aromatic promoter other than a phenolic-hydroxy-aromatic compound, both promoters having B.P. higher than water, being inert to the strong base, and being substantially insoluble in the liquid treated, and mixtures of alkyl phenolates with alkali salts of fatty acids with 3-5 C atoms being excluded. Any mercaptan not removed may be converted to disulphide. Specified bases are potassium and sodium hydrates or carbonates, ammonia, and quaternary ammonium bases. Promoters suitable are those specified in Specifications 492,789, 494,450, 494,451, 499,678, 503,644, 503,645, 506,574 and 509,669, e.g. aliphatic alkanolamines and amino-alkylamines ; diaminoalcohols; glycols and amino-glycols; alkyl glycerines ; mono-methyl glyceryl ether ; diamino-, dihydroxy-, or amino-hydroxy-alkyl ethers or thio-ethers; alkali metal salts of fatty acids with 3-5 C atoms or in the case of potassium salts 1-6 C atoms ; amino- or hydroxyfatty acids containing 2-7 C atoms ; phenyl acetic acid; hydroxy- or amino-phenyl acetic acid; and alkyl phenols. Alkyl phenols may be replaced in part by amino-phenols, naphthols, amino- and/or alkyl-naphthols, and polyhydroxy-phenolic aroma oxidation inhibitors, e.g. hydroquinones, catechols, and pyrogallols. The extraction may be effected at 32-140‹ F. but is usually at atmospheric temperature ; it may be countercurrent. The spent solution is preferably regenerated by steaming as described in Specification 519,397. Tables and diagrams are given showing the properties or effects of known solutions with those of the present invention.