Process for production of hydroquinone
AssigneeMitsui Petrochemicals Industry, Ltd.
InventorsNobuo Kurosaka, Makoto Yasuda, Tadateru Murakami
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Abstract
High quality hydroquinone is produced from p-diisopropylbenzene dihydroperoxide at a high yield according to the disclosed process. The p-diisopropylbenzene dihydroperoxide is decomposed in the presence of an acid catalyst and the concentration of the hydroperoxide is maintained in the range of 0.1 to 1% by weight; the remaining hydroperoxide in the decomposition step is further subjected to an acid decomposition prior to the recovery of the formed hydroquinone product.
Claims13
A process for producing hydroquinone comprising the sequential steps of:
- (1) decomposing p-diisopropylbenzene dihydroperoxide in the presence of a water-soluble acid catalyst selected from sulfuric acid, phosphoric acid, and perchloric acid at a temperature of about 20.degree. C. to about 90.degree. C. while maintaining the hydroperoxide concentration within the range of about 0.1 to about 1% by weight;
- (2) distilling the reaction mixture, after removing the acid catalyst therefrom, whereby low boiling point components contained in the reaction mixture are removed from the reaction mixture;
- (3) further subjecting the remaining hydroperoxide from decomposition step (1) to an acid decomposition inside the distillation column, or in a downstream portion of the distillation column, and removing the low boiling point components, including water, whereby the content of the hydroperoxide is decreased;
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- (4) removing the thus formed hydroquinone from the distillation residue.
A process for producing hydroquinone comprising the sequential steps of:
- (1) decomposing p-diisopropylbenzene dihydroperoxide in the presence of a water-soluble acid catalyst selected from sulfuric acid, phosphoric acid, and perchloric acid at a temperature of about 20.degree. C. to about 90.degree. C. and maintaining the concentration of the hydroperoxide in the range of about 0.1 to about 1% by weight;
- (2) distilling the reaction mixture, after removing the acid catalyst therefrom, whereby low boiling point components contained in the reaction mixture are removed from the reaction mixture in the presence of a solvent which has a boiling point higher than that of water and which is insoluble or only slightly soluble in water but is capable of dissolving hydroquinone;
- (3) further subjecting the remaining hydroperoxide from the decomposition step to an acid decomposition in the plural distillation columns during the removal of the low boiling point components and/or said solvent whereby the content of the hydroperoxide is decreased, and solvent is recovered as an azeotrope;
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- (4) recovering the thus formed hydroquinone from the distillation residue.
A process for producing hydroquinone comprising the sequential steps of:
- (1) decomposing p-diisopropylbenzene dihydroperoxide in the presence of sulfuric acid or phosphoric acid, and maintaining the concentration of the hydroperoxide in the range of about 0.1 to about 1% by weight;
- (2) distilling the reaction mixture at a temperature of about 20.degree. C. to about 90.degree. C., after removing said sulfuric acid or phosphoric acid therefrom, whereby low boiling point components contained in the reaction mixture are removed from the reaction mixture;
- (3) further subjecting the remaining hydroperoxide from the decomposition step to an acid decomposition in the distillation column during the removal of the low boiling point components where by the content of the hydroperoxide is decreased;
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- (4) recovering the thus formed hydroquinone from the distillation residue.
Dependencies are inferred from the claim text.