Sumitomo Chemical Company, Limited

Hideaki Suda

Hirokazu Hosaka

Iwao Dohgane

Yuji Ueda

Kunihiko Tanaka

Kenji Tanimoto

Takashi Chinuki

Yukimichi Nakao

Seiya Imada

Hideki Yanagihara

Hirotoshi Nakanishi

Tatsumi Nuno

Hiroshige Tomita

Tatsuo Kanda

Hiromu Hida

Seiichi Akutsu

Masayuki Maeyashiki

A process for recovery of urea from a phenolic solution thereof which comprises adding an organic solvent selected from the group consisting of aliphatic amides, ethers, carbon disulfide and dimethylsulfoxide to the said phenolic solution and collecting the separated crystals of urea from the resultant mixture. The process is characteristic in recovering urea in the solid state without the use of water but a particular organic solvent.

Process for recovery of urea from its phenolic solution

Resorcinol and hydroquinone are recovered in mixture at a high purity from a solution containing resorcinol and hydroquinone, especially, a solution resulting from cleavage of oxidation products of isopropylbenzene and successive distillation of the cleavage product thereby to remove lower and higher boiling components therefrom, by adding 0.5 to 20 parts by weight of at least one solvent selected from aromatic hydrocarbons, aromatic hydrocarbons having lower alkyl substituent groups, and aliphatic hydrocarbons having 7 to 10 carbon atoms to one part by weight of said solution, if necessary, together with 1 to 30% by weight of at least one compound selected from ketones having 3 to 10 carbon atoms, alcohols having 1 to 5 carbon atoms and aliphatic esters having 3 to 5 carbon atoms, based on the weight of the organic solvent, dissolving the solution into the organic solvent by heating, separating a mixture of resorcinol and hydroquinone as a solid phase from the organic solvent layer after slow cooling, and recovering the solid phase as a product. The resorcinol and hydroquinone in the organic solvent layer are further recovered through extraction with water. When water is used together with the organic solvent from the beginning of extraction, the resorcinol and hydrocarbon are obtained in an aqueous layer.

Process for recovering resorcinol and hydroquinone in mixture

Sulfonylamide derivatives of the formula,

Process for producing sulfonylamides

Meta-and/or paradiisopropylbenzene dihydroperoxides are continuously produced by oxidizing meta-and/or paradiisopropylbenzenes in liquid phase through contact with oxygen or a gas containing oxygen, while keeping the concentration of meta-and/or paradiisopropylbenzene monohydroperoxides of the oxidation product solution in a range of 20 to 40% by weight.

Process for the continuous production of dihydroperoxides

Impurities, that is, by-products, in an oxidation product solution obtained by oxidation of diisopropylbenzene by molecular oxygen or in the oxidation product solution freed from diisopropylbenzene dihydroperoxide, are removed by extracting the by-products such as carbinols, ketones and styrenes from the solution with a mixture of an aqueous alkaline solution and at least one of alcohols having 1 to 3 carbon atoms such as methanol, ethanol, and isopropanol, as an extracting reagent at a temperature of 20.degree. to 80.degree.C.

Process for removing impurities in an oxidation mixture

In a process for the production of hydroperoxides by the oxidation of an aromatic hydrocarbon having at least one tertiary carbon atom with oxygen or an oxygen containing gas in the presence of an aqueous alkaline solution, an improvement is made in that the oxidation is effected in an emulsion phase which is caused by powerfully mixing all or a part of the materials to be brought into the oxidation reaction only by the aid of the hydroperoxides formed in the reaction, whereby enhancing the reaction rate with safety.

Process for the production of hydroperoxides

Dihydroperoxides of dialkylaromatic hydrocarbons are separated in high yield from an aqueous alkaline solutions of hydroperoxides containing the dihydroperoxides by adding 0.01 to 1 % by weight of a compound having a nitrogen base, such as ammonia and aromatic amines, to the solution, based on the weight of the solution, thereby stabilizing the dihydroperoxides in the solution, and separating the dihydroperoxides therefrom by extraction.

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Takaishi, Japan

Hideaki Suda