New Japan Chemical Co., Ltd.

Sk Njc Co., Ltd.

Mikio Nakazawa

Hiroshi Manami

Kango Fujitani

Shigeo Miki

Tatsuo Kyuma

Toshihiro Mizutani

Taiichiro Iwamura

Hiroshi Itoh

Yasuhisa Yoshida

Akihiro Nishiuchi

This invention provides a process for preparing cyclohexanedimethanol comprising hydrogenating a cyclohexanedicarboxylic acid dialkyl ester by a fixed-bed continuous reaction in the presence of a preformed copper-containing catalyst under the conditions of reaction temperature of 200 to 280&deg; C., hydrogen pressure of 185 to 300 kgf/cm,and hydrogen gas feed rate of 1 to 40 cm/s in terms of superficial linear velocity, the cyclohexanedicarboxylic acid dialkyl ester being prepared, typically, by ring hydrogenating of an aromatic dicarboxylic acid dialkyl ester in the presence of a preformed supported ruthenium catalyst by a fixed-bed continuous reaction.

Process for the preparation of cyclohexanedimethanol

Thermoplastic resin composition and a method of molding the same

Disclosed is a process for preparing a diphenyl sulfonetetracarboxylic acid, the process comprising oxidizing a tetramethyldiphenyl sulfone with oxygen or an oxygen-containing gas in an aliphatic monocarboxylic acid having 2 to 10 carbon atoms in the presence of a catalyst consisting essentially of a cobalt component, a manganese component and a bromine compound wherein the weight ratio of manganese metal to cobalt metal is in the range of approximately 0.01 to 0.5.

Process for preparing diphenyl sulfonetetracarboxylic acid

Disclosed is a method for purifying a crude diphenylsulfone tetracarboxylic acid which comprises the steps of dissolving a crude diphenyolsulfone tetracarboxylic acid in a solvent mixture of water and acetic acid and recrystallizing the crude to obtain a highly purifed diphenylsulfone tetracarboxylic acid.

Method for purifying a crude diphenylsulfone tetracarboxylic acid

Disclosed is a process for preparing a polycarboxylic acid, the process comprising subjecting a Diels-Alder reaction product of maleic anhydride and a diene and/or the corresponding acid to oxidative cleavage using hydrogen peroxide in the presence of at least one catalyst selected from the group consisting of tungstic acid, molybdic acid and heteropoly acids thereof.

Process for preparing polycarboxylic acid

In preparing a diarylsulfone by condensing sulfuric acid or an aromatic sulfonic acid with an aromatic compound having at least one replaceable hydrogen atom on the aromatic ring, the process of the present invention is characterized in that the condensation reaction is carried out in the presence of at least one catalyst selected from the group consisting of a tungstic acid, molybdic acid and heteropoly acid thereof.

Process for preparing diarylsulfones

This invention provides a process for preparing carboxylic acid, the process comprising subjecting an oxidation product produced by reacting a peroxide with (a) unsaturated aliphatic monocarboxylic acid having at least one unsaturated bond in the carbon chain and containing 6 to 24 carbon atoms or its ester or (b) cyclic and/or acyclic aliphatic olefin having at least one unsaturated bond in the carbon chain to oxidation by oxygen or oxygen-containing gas in the presence of a catalyst comprising (i) at least one heavy metal compound and (ii) at least one member selected from the group consisting of a bromine compound and a chlorine compound.

Process for preparing carboxylic acid

A process is provided for preparing an N,N-dialkyl aromatic amine by reacting an aromatic amine of the formula ##STR1## wherein R is a hydrogen atom or a lower alkyl group with a lower alcohol in the presence of at least one catalyst selected from sulfuric acid and compounds being capable of forming sulfuric acid during the reaction. The essential features of this process are characterized by:

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Uji, Japan

Mikio Nakazawa