Teijin Limited

Sumitomo Chemical Company, Limited

Yutaka Fujita

Toru Sawaki

Koji Nakagawa

Yuitsu Honda

Masao Sada

Tadahisa Sasano

A process for preparing a mixture of organic carboxylic acids and esters thereof consisting predominantly of epsilon-hydroxycaproic acid, adipic acid, formylvaleric acid, and esters of these acids by oxidizing a mixture of cyclohexane, cyclohexanol and cyclohexanone with molecular oxygen, which comprises withdrawing at least a part of the oxidation reaction mixture from the oxidation reaction system, extracting the organic carboxylic acids and esters thereof from the oxidation reaction mixture until the concentration of the total carboxyl groups of said oxidation reaction mixture is reduced to a value not greater than 1.2 gram equivalents per liter of the reaction mixture, the several ester bonds of the esters contained in reaction mixture being considered to be carboxyl groups, recycling to the oxidation reaction system the resulting liquid extraction residue containing unreacted cyclohexane, cyclohexanol and cyclohexanone and carrying out the oxidation reaction, while recovering the carboxylic acids and esters thereof from the liquid extract.

Process for the preparation of mixture consisting predominantly of .epsilon

Lactones are separated from a mixture of (a) at least one member selected from the group consisting of hydroxy acids wherein the OH group and the COOH group are bonded through 3 or 4 carbon atoms, lactones derived therefrom, lower polymers of said hydroxy acids and/or said lactones and esters of said hydroxy acids and/or said lactones and (b) at least one member selected from the group consisting of hydroxy acids wherein the OH group and the COOH group are bonded through 5 carbon atoms, lactones derived therefrom, lower polymers of said hydroxy acids and/or said lactones and esters of said hydroxy acids and/or said lactones, by heating said mixture in the presence of one or more monovalent or bivalent aliphatic or alicyclic alcohols under the conditions so as to remove the lactones from said (a) by distillation.

Method for separating lactones from a mixture containing lactones

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Iwakuni, Japan

Yutaka Fujita