Abstract: A purification method of dihydroxybenzene comprising the following steps, for obtaining purified dihydroxybenzene from crude dihydroxybenzene containing at least isopropenylphenol and hydroxyacetophenone as impurities: first extraction step, distillation step, second extraction step, and recovery step.

Abstract: There is provided a method for handling an aqueous solution containing a water-soluble substance that changes into a water-insoluble substance over time, including a step of bringing the aqueous solution to be treated containing the water-soluble substance that changes into the water-insoluble substance over time into contact with a water-insoluble organic solvent, and extracting the water-soluble substance into the water-insoluble organic solvent. Preferably, the water-soluble substance is alkylbenzene hydroperoxide, and the water-insoluble substance is alkylbenzene hydroperoxide-derived alcohol. Preferably, the aqueous solution to be treated is an alkaline aqueous phase separated in a water-washing step in a process of manufacturing the alkylbenzene hydroperoxide that has an alkali extraction step, the water-washing step, an oxidation step, and a reaction solution separation step.

Abstract: A purification method of dihydroxybenzene comprising the following steps, for obtaining purified dihydroxybenzene from crude dihydroxybenzene containing at least isopropenylphenol and hydroxyacetophenone as impurities: first extraction step: water is added to crude dihydroxybenzene to prepare a dihydroxybenzene aqueous solution A, then, the solution is subjected to extraction by allowing it to contact with an extraction solvent (1), to be separated into a first fraction containing dihydroxybenzene, hydroxyacetophenone and water and a second fraction containing isopropenylphenol and the extraction solvent (1), distillation step: the first fraction obtained in the first extraction step is subjected to distillation, to be separated into a third fraction containing water and a fourth fraction containing dihydroxybenzene and hydroxyacetophenone, then, the fourth fraction is subjected to distillation, to be separated into a fifth fraction as purified dihydroxybenzene and a sixth fraction as dihydroxybenzene contain

Abstract: A process for producing a phenol, which comprises the following steps of: (1) oxidizing an alkylbenzene with an oxygen-containing gas to obtain an oxidation reaction mixture containing a hydroperoxide; (2) subjecting the oxidation reaction mixture to extraction operation with an alkaline aqueous solution to obtain an extract containing the hydroperoxide; (3) subjecting the extract obtained in the step (2) to extraction operation with an organic solvent to obtain an extract containing the hydroperoxide; (4) subjecting the extract obtained in the step (3) to water washing to obtain an oil layer containing the hydroperoxide, in which a content of the alkali has been reduced; and (5) subjecting the hydroperoxide contained in the oil layer obtained in the water washing step (4) to acidolysis to obtain a phenol, wherein a concentration of the hydroperoxide to be subjected to the water washing in the step (4), is 20% by weight or less.

Abstract: A process for producing a phenol, which comprises the following steps of: (1) oxidizing an alkylbenzene with an oxygen-containing gas to obtain an oxidation reaction mixture containing a hydroperoxide; (2) subjecting the oxidation reaction mixture to extraction operation with an alkaline aqueous solution to obtain an extract containing the hydroperoxide; (3) subjecting the extract obtained in the step (2) to extraction operation with an organic solvent to obtain an extract containing the hydroperoxide; (4) subjecting the extract obtained in the step (3) to water washing to obtain an oil layer containing the hydroperoxide, in which a content of the alkali has been reduced; and (5) subjecting the hydroperoxide contained in the oil layer obtained in the water washing step (4) to acidolysis to obtain a phenol, wherein a concentration of the hydroperoxide to be subjected to the water washing in the step (4), is 20% by weight or less.

Abstract: A process for producing an alkyl aromatic hydroperoxide, which comprises oxidizing an alkyl aromatic compound with an oxygen-containing gas in the presence of a water-soluble iron compound, wherein a concentration of the iron compound in the oxidation reaction system is 0.0001 to 10 ppm by weight in terms of iron metal.

Abstract: A process for producing a hydroxyaromatic compound by oxidizing an alkyl group-substituted aromatic hydrocarbon to a hydroperoxyaromatic compound and decomposing the hydroperoxyaromatic compound to the hydroxyaromatic compound in which the step of neutralizing the reaction mixture containing the hydroxyaromatic compound with an aqueous alkali solution is conducted so that an aqueous layer, which is obtained by mixing an oil layer of the neutralized mixture and deionized water in a volume ratio of the oil layer to the deionized water of 2:1 to obtain an oil/water mixture and allowing the oil/water mixture to stand still, may have a pH falling within the range of from 4.5 to 5.5, improves the yield of the hydroxyaromatic compound product while suppressing by-production of heavy substances.

Abstract: There are provided: (I) a process for preparing an extract containing at least one hydroperoxide, which comprises the steps of: (1) oxidizing an aromatic hydrocarbon substituted with an alkyl group to obtain a liquid reaction mixture, and (2) extracting at least one hydroperoxide in the liquid reaction mixture to obtain an extract having a concentration of acetone of not more than 1% by weight: and (II) a process for preparing an extract containing at least one hydroperoxide, which comprises the steps of, (1) oxidizing an aromatic hydrocarbon substituted with an alkyl group to obtain a liquid reaction mixture, and (2) extracting at least one hydroperoxide with an aqueous alkali solution having an A value of not more than 10 to obtain an extract.

Abstract: A process for producing a hydroxyaromatic compound by oxidizing an alkyl group-substituted aromatic hydrocarbon to a hydroperoxyaromatic compound and decomposing the hydroperoxyaromatic compound to the hydroxyaromatic compound in which the step of neutralizing the reaction mixture containing the hydroxyaromatic compound with an aqueous alkali solution is conducted so that an aqueous layer, which is obtained by mixing an oil layer of the neutralized mixture and deionized water in a volume ratio of the oil layer to the deionized water of 2:1 to obtain an oil/water mixture and allowing the oil/water mixture to stand still, may have a pH falling within the range of from 4.5 to 5.5, improves the yield of the hydroxyaromatic compound product while suppressing by-production of heavy substances.

Abstract: There are provided: