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摘要

A process for extracting from aqueous solution the alkali metal or ammonium salt of a phenol, naphthol, anthrol or phenanthrol or the corresponding thiol, which comprises contacting an aqueous alkaline or neutral solution of the alkali metal or ammonium salt, in which is dissolved an alkali metal or ammonium fluoride, chloride, bromide, hydroxide, nitrate, nitrite, sulphate, sulphite, sulphide, thiosulphate, phosphate, hydrogen phosphate, carbonate, bicarbonate, cyanate, cyanide, thiocyanate, borate, chlorate, chlorite, hypochlorite, perchlorate, chromate, dichromate or permanganate, with a partially water-miscible organic solvent so as to transfer aqueous solution of the alkali metal or ammonium salt of the phenol, naphthol, anthrol or phenanthrol or corresponding thiol into the solvent while retaining separate aqueous and solvent phases, and thereafter separating the solvent phase containing the alkali metal or ammonium salt and water from the aqueous phase, the ratio of solvent to water in the separated solvent phase being from 0.5:1 to 10:1 w/w.