Mitsubishi Gas Chemical Company, Inc.

Koichi Kida

Hirofumi Higuchi

Shuji Ebata

Takafumi Abe

Yoshio Kawai

Hiroyuki Hirayama

Yoshiharu Suzuki

Tetsuo Aoyama

Yoshikazu Shima

Takako Uchiyama

Yutaka Tamura

Hideo Ikarashi

Makoto Komatsu

Mitsuharu Kitamura

Hiroshi Machida

Susumu Fujiyama

Seiji Uchiyama

Toshio Kondo

Tsukasa Toki

Takahiro Ojima

Jiro Ishikawa

A method of producing methyl methacrylate comprises Step 1 of producing acetone cyanhydrin from hydrogen cyanide and acetone; Step 2 of producing .alpha.-hydroxyisobutyramide by hydrating acetone cyanhydrin; Step 3 of producing methyl .alpha.-hydroxyisobutyrate and ammonia by a reaction of .alpha.-hydroxyisobutyramide and methanol; Step 4 of producing methyl methacrylate by dehydrating methyl .alpha.-hydroxyisobutyrate; and Step 5 of producing hydrogen cyanide in vapor phase by reacting methanol and the ammonia obtained in Step 3 over a solid catalyst in the presence of molecular oxygen. By using methanol in the step 3, the conversion ratio of .alpha.-hydroxyisobutyramide into methyl .alpha.-hydroxyisobutyrate can be increased because the equilibrium of the reaction is easily sifted toward the product side by removing ammonia being produced from the reaction system. The use of methanol in the step 3 produces additional advantages of efficiently linking the steps to eliminate the steps for separation and purification, thereby reducing the production cost.

Integrated method for producing methyl methacrylate and hydrogen cyanide

A method for preparing an alkylbenzoic acid is herein disclosed which comprises subjecting an alkylbenzene having at least two alkyl groups of 1 to 3 carbon atoms to a liquid phase oxidative reaction with a molecular oxygen-containing gas in the presence of a soluble heavy metal catalyst to convert one alkyl group into a carboxylic acid, thereby preparing the alkylbenzoic acid, and impurities contained in the alkylbenzene recovered from the reaction solution are removed therefrom by distillation, water washing, alkali washing, a treatment with an anion exchange resin or a treatment with a solid adsorbent, and the impurities-free fraction is reused as a raw material. Furthermore, the conversion of the desired product is regulated to 25% or less in the liquid phase oxidative reaction, whereby the reaction is carried out in a boiling heat removal state and reaction heat is removed as the heat of vaporization. Thus, there can be decreased a dicarboxylic acid secondarily produced during the manufacture of the alkyl-benzoic acid which is a monocarboxylic acid by subjecting the alkylbenzene to the liquid phase oxidation, whereby problems such as the trouble of equipment operation and the deterioration of product quality can be solved.

Method for preparing alkylbenzoic acid

A process for producing a 4-formyl-4'-methylbiphenyl from a biphenyl which comprises conducting the carbonylation of the biphenyl with carbon monoxide in the presence of a HF-BF.sub.3 catalyst in a carbonylation reactor to obtain the resulting reaction product solution containing a 4-formylbiphenyl, separating the 4-formylbiphenyl from the reaction product solution, hydrogenating the separated 4-formylbiphenyl to obtain a 4-methylbiphenyl, recycling the 4-methylbiphenyl to the carbonylation reactor, and then conducting both the carbonylation of the biphenyl with carbon monoxide to obtain a formylbiphenyl and the carbonylation of the 4-methylbiphenyl with carbon monoxide to obtain a 4-formyl-4'-methylbiphenyl simultaneously in the presence of the HF-BF.sub.3 catalyst in the carbonylation reactor.

Process for producing 4-formyl-4'-methylbiphenyl from biphenyl

Carboxylic acid esters and formamide are efficiently obtained by reacting carboxylic acid amides and formic acid esters, or by reacting carboxylic acid amides, alcohols and carbon monoxide in the presence of a dehydrated condensate of carboxylic acid amide with an alkali metal hydroxide or an alkaline earth metal hydroxide catalyst.

Process for production of carboxylic acid esters and formamide

A process for preparing an amide by hydrating a cyanohydrin with a denatured manganese dioxide catalyst. The catalyst is prepared by reacting an aqueous permanganate solution and an aqueous manganese (II) compound solution in an acidic aqueous solution at a temperature of 70.degree. C. to 150.degree. C.

Process for producing a denaturated manganese dioxide catalyst for the

Disclosed is a process for producing methyl methacrylate which comprises:

Process for producing methyl methacrylate

A process for producing .alpha., .beta.-unsaturated carboxylic acid ester which comprises catalytically reacting .alpha.-hydroxycarboxylic acid ester with crystalline aluminosilicate catalyst, and then catalytic reacting the resulting reaction product with solid acid catalyst. According to the process, .alpha., .beta.-unsaturated carboxylic acid ester of a high purity, and a high quality, without by-product, can be produced efficiently.

Process for preparing .alpha., .beta.-unsaturated carboxylic acid ester

A process for producing a denatured manganese dioxide for the hydration reaction of cyanohydrins comprising reacting an aqueous permanganate salt solution and an aqueous manganese (II) compound in an acidic aqueous solution at a temperature of 70.degree. C. to 130.degree. C. is disclosed. The manganese dioxide catalyst obtained by the process exhibits a high activity over a long period in the preparation of an amide by the hydration of the corresponding cyanohydrin.

A process for producing an .alpha.-hydroxyisobutyric acid which comprises hydrolyzing .alpha.-hydroxyisobutyric acid ester in the presence of an organic sulfonic acid catalyst, using an .alpha.-hydroxyisobutyric acid ester as the starting material. According to said process, .alpha.-hydroxyisobutyric acid can be efficiently produced.

Process for producing .alpha.-hydroxyisobutyric acid

A process for production of 2,6-dimethylnaphthalene is disclosed; comprising the steps: (1) an acylation step where 2,4-dimethylisobutyrophenone is produced from m-xylene, propylene and carbon monoxide: (2) a hydrogenation step where the carbonyl group of the above 2,4-dimethylisobutyrophenone is hydrogenated: and (3) a dehydrogenation and cyclization step where the above hydrogenated product is subjected to dehydrogenation and cyclization to produce the desired 2,6-dimethylnaphthalene. The process enables efficiently producing high quality or high purity 2,6-dimethylnaphthalene.

Process for production of 2,6-dimethylnaphthalene

A process for production of 2,6-dimethylnaphthalene is disclosed, comprising the steps: (1) an acylation step where p-tolyl sec-butyl ketone is produced from toluene, n-butene and carbon monoxide: (2) a hydrogenation step where the carbonyl group of the p-tolyl sec-butyl ketone is hydrogenated: and (3) a dehydrogenation and cyclization step where the hydrogenated product obtained above is subjected to dehydrogenation and cyclization to produce the desired 2,6-dimethylnaphthalene. The process enables efficiently producing a high quality or high purity 2,6-dimethylnaphthalene.

Carboxylic acid esters and formamide are efficiently obtained for reacting carboxylic acid amides and formic acid esters, or carboxylic acid amides, alcohols and carbon monoxide in the presence of an alkaline earth metal oxide catalyst.

Disclosed is a process for producing .alpha.-hydroxy-carboxylic acid amide represented by the formula (I): ##STR1## wherein R.sup.1 and R.sup.2 are as defined in the specification, by a catalytic hydration reaction of cyanohydrin represented by the formula (II): ##STR2## which comprises using a modified manganese dioxide containing one or more of an alkali metal element and an alkaline earth element in an amount of 0.05 to 0.5 based on the manganese element in terms of atomic ratio.

Process for producing alpha-hydroxycarboxylic acid amide

A commercially economical process for preparing a carboxylic acid ester from a carboxylic acid amide is disclosed. The process is very meritorious, since it produces neither ammonia nor ammonium sulfates. Rather, the process by-produces formamides which are very useful compounds as solvents. Further, formamide can easily be converted to hydrogen cyanide by dehydration. The process comprises reacting a carboxylic acid amide with a formic acid ester and/or methanol and carbon monoxide in the presence of a bicyclic amidine or tertiary amine catalyst and optionally in the co-existence of a metal carbonyl. An industrial process for preparing methyl methacrylate which is a materialization of the process shown above is described in detail referring to a figure.

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Niigata, Japan

Koichi Kida