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AssigneeSumitomo Chemical Company, Limited
InventorsHirokazu Hosaka, Kenji Tanimoto, Hiromichi Okabe, Kunthiko Tanaka, Yuji Ueda, Iwao Dohgane
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A method for extracting a dihydroperoxide of a dialkylbenzene of the formula, ##STR1## wherein each R.sub.1, R.sub.2, R.sub.3 and R.sub.4 is independently a lower alkyl group, from an aqueous alkali solution of the said dihydroperoxide with at least one organic solvent selected from the group consisting of C.sub.4 -C.sub.10 ketones, C.sub.4 -C.sub.10 ethers and C.sub.4 -C.sub.8 alcohols, which comprises extracting the dihydroperoxide by a countercurrent multi-stage extraction at a temperature between 0.degree. and 85.degree. C with a temperature gradient, the aqueous alkali solution being fed to the lower temperature zone, the organic solvent being fed to the higher temperature zone, and each aqueous alkali solution and organic solvent being fed countercurrently, whereby the dihydroperoxide is obtained in the form of organic solvent solution from the lower temperature zone.
A method for extracting a dihydroperoxide of a dialkylbenzene of the formula, ##STR3## wherein each R.sub.1, R.sub.2, R.sub.3 and R.sub.4 is independently isopropyl or sec.butyl, from an aqueous alkali solution of the said dihydroperoxide with at least one organic solvent selected from the group consisting of C.sub.4 -C.sub.10 ketones, C.sub.4 -C.sub.10 ethers and C.sub.4 -C.sub.8 alcohols, which comprises extracting the dihydroperoxide by a countercurrent multi-stage extraction with a temperature gradient between each stage and with all of the extractions being conducted at a temperature of from 0.degree. to 85.degree. C, the aqueous alkali solution being fed to the lower temperature zone, the organic solvent being fed to the higher temperature zone with said lower temperature being from 0.degree. to 50.degree. C, and said higher temperature being from 50.degree. to 85.degree. C, and each aqueous alkali solution and organic solvent being fed countercurrently, whereby the dihydroperoxide is obtained in the form of organic solvent solution from the lower temperature zone.
A method for extracting a dihydroperoxide of a dialkylbenzene of the formula, ##STR4## wherein each R.sub.1, R.sub.2, R.sub.3 and R.sub.4 is independently isopropyl or sec.-butyl, from an aqueous alkali solution of the said dihydroperoxide, which comprises feeding the aqueous alkali solution to one side of an extraction zone together with countercurrent feed of at least one organic solvent selected from the group consisting of C.sub.4 -C.sub.10 ketones, C.sub.4 -C.sub.10 ethers and C.sub.4 -C.sub.8 alcohols to the other side of extraction zone, the extraction zone having a multi-stage with a temperature gradient between each stage and with all of the extractions being conducted at a temperature from 0.degree. to 85.degree. C, the aqueous alkali solution being fed to a lower temperature zone, and the organic solvent being fed to a higher temperature zone with said lower temperature being from 0.degree. to 50.degree. C, and said higher temperature being from 50.degree. to 85.degree. C, whereby the dihydroperoxide is obtained in the form of the organic solvent solution from the lower temperature zone.
Dependencies are inferred from the claim text.
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No related US applications are recorded in the indexed filing history.
Preparation of peroxy compounds: separation; Purification; Stabilisation; Use of additives
Acyclic or carbocyclic compounds
Term ended 22 Nov 1994 (estimated)
USPTO file history isn’t available for this patent, so only indexed dates are shown.
The present invention relates to a method for extracting and recovering dialkylbenzene dihydroperoxide from aqueous alkali solutions thereof with a high efficiency. More particularly, the invention relates to an industrially advantageous method for extracting and recovering the dihydroperoxide in a high yield and high purity by carrying out countercurrent multistage extraction with a temperature gradient from O.degree. to 85.degree. C.
A method which comprises oxidizing dialkylbenzenes into dihydroperoxide thereof and cleaving the dihydroperoxide into resorcinol and/or hydroquinone is attracting attention as a novel and advantageous preparation of resorcinol and/or hydroquinone.
The alkylbenzenes which are used for this purpose include for example diisopropylbenzene, di-sec-butylbenzene, isopropyl-sec-butylbenzene and the like, of which diisopropylbenzene is most popular. The present invention will be illustrated with reference to the diisopropylbenzene.
As mentioned above, the present invention was illustrated with reference to diisopropylbenzene, but this invention is of course applicable similarly to other compounds represented by the formula (I).
FIG. 1 is one example of the embodiments of the present invention. The numbers 1 to 4 each represents a mixer-settler and the symbols A and B represent the aqueous caustic soda liquor inlet and the organic solvent inlet.
The present invention will be illustrated specifically with reference to the following examples. All percentages and parts in the examples are by weight.
Countercurrent multi-stage extraction was carried out using a combination of four mixer-settler type extractors (Nos. 1 to 4) as shown in FIG. 1. DHPO-containing aqueous alkali solution as a material was prepared by extracting the oxidation solution of m-diisopropylbenzene with an 8% aqueous caustic soda solution and then extracting the aqueous extract with methyl isobutyl ketone (MIBK) at 20.degree. C to remove CHPO and the like in advance. The DHPO-content and CHPO-content of the solution as a material were 11.3 and 0.5%, respectively.
The aqueous caustic soda solution was charged in the mixer-settler No. 1 at the liquor inlet A at a feed rate of 100 parts/hr. The extracting solvent, MIBK, was charged in the mixer-settle No. 4 at the liquor inlet B at a feed rate of 200 parts/hr.