Mitsui Chemicals, Inc.

Koji Takamatsu

Masaaki Sasaki

Takeshi Fukuda

Hideki Sone

Tetsuya Nakano

Satoshi Kato

Hiroshi Takeuchi

Kazuhiro Kosumi

Yoshiki Shimokawatoko

Yasushi Kotaki

Takashi Kanno

Koichi Murayama

Masashi Shimamoto

Tomohiro Kano

The method for producing pentamethylene diisocyanate includes a reaction step, in which carbonyl chloride is allowed to react with pentamethylenediamine to produce a reaction mixture containing pentamethylene diisocyanate and a tar component containing a chlorine-containing component; a heating step, in which the reaction mixture is heated; and a purification step, in which the reaction mixture after the heating step is purified to separate the pentamethylene diisocyanate from the tar component, wherein in the heating step, the reaction mixture is heated without removing the tar component from the reaction mixture.

Method for producing pentamethylene diisocyanate

Xylylene dicarbamate contains impurities represented by formulas (1) to (4) below at a ratio of less than 100 ppm as a total amount thereof on a mass basis.  (In the above-described formulas (1) to (4), R represents a monovalent hydrocarbon group.).

Xylylene dicarbamate, method for producing xylylene diisocyanate, xylylene diisocyanate, and method for reserving xylylene dicarbamate

Xylylene dicarbamate contains impurities represented by formulas (1) to (4) below at a ratio of less than 100 ppm as a total amount thereof on a mass basis.  (In the above-described formulas (1) to (4), R represents a monovalent hydrocarbon group.)

A method for producing xylylene diisocyanate includes a thermal decomposition step of thermally decomposing xylylene dicarbamate; a first separation step of separating, from the thermal decomposition product obtained in the thermal decomposition step, an isocyanate-containing component containing xylylene diisocyanate as a main component and an alcohol-containing component containing alcohol as a main component and containing xylylene diisocyanate as a subcomponent; a second separation step of separating xylylene dicarbamate and alcohol from the alcohol-containing component obtained in the first separation step; and a returning step of returning xylylene dicarbamate obtained in the second separation step to the thermal decomposition step.

Method for producing xylylene diisocyanate and system for producing xylylene diisocyanate

A method for producing carbamate including a urea production step; a carbamate-forming step; an ammonia separation step of absorbing the gas with water in the presence of carbonate to produce a gas absorption water, and separating ammonia; an aqueous alcohol solution separation step of separating an aqueous alcohol solution from the gas absorption water; an ammonia/carbon dioxide separation step of separating carbon dioxide gas from the aqueous ammonia solution in the gas absorption water from which the aqueous alcohol solution is separated; an aqueous ammonia solution reusing step of mixing the aqueous ammonia solution and carbonate with the water to be used for production of the gas absorption water.

Method for producing carbamate, method for producing isocyanate, carbamate production system, and isocyanate production system

A method for producing tolylene diisocyanate includes: mixing a first diaminotoluene containing 2,4-diaminotoluene and 2,6-diaminotoluene at a first isomer ratio and a second diaminotoluene containing 2,4-diaminotoluene and/or 2,6-diaminotoluene at a second isomer ratio that is different from the first isomer ratio so as to prepare mixed diaminotoluene; producing tolylene dicarbamate by reaction of the mixed diaminotoluene, urea and/or N-unsubstituted carbamic acid ester and alcohol; and thermally decomposing the tolylene dicarbamate.

Method for producing tolylene diisocyanate

A method for producing toluenedicarbamate includes a carbamate production process of producing toluenedicarbamate by reaction between toluenediamine, urea, and/or N-unsubstituted carbamic acid ester, and alcohol; and a benzoyleneurea reduction process of reducing a disubstituted benzoyleneurea and a derivative thereof to 10 mol or less relative to 100 mol of toluenedicarbamate, wherein the disubstituted benzoyleneurea is represented by formula (1) below and has a methyl group and an amino group: 

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Omuta, Japan

Koji Takamatsu