Asahi Kasei Kabushiki Kaisha

Asahi Kasei Chemicals Corporation

Takeharu Sasaki

Nobuhisa Miyake

Masaaki Shinohata

Yusuke Ishii

Yusuke Sakurai

Yuji Kosugi

Koichi Nakaoka

Atsushi Ohkubo

Kazuhiro Takagaki

Tsubasa Uematsu

A method is provided for collecting a compound of formula (III) (in which R31 is a monovalent to trivalent organic group and n31 is an integer of 1 to 3) from a liquid phase component that is formed as a by-product in a method for producing a compound of general formula (I) (in which R11 is a monovalent to trivalent organic group and n11 is an integer of 1 to 3), wherein the collection method contains steps (1) to (3) or steps (A) and (B), and step (4). Step (1): a step for reacting the liquid phase component with at least one active hydrogen-containing compound in a reactor. Step (2): a step for returning a condensed liquid obtained by cooling gas phase components in the reactor to the reactor. Step (3): a step for discharging gas phase components that are not condensed in the step (2) to the outside of the reactor. Step (A): a step for mixing the liquid phase component, water, and a compound of general formula (III). Step (B): a step for reacting the liquid phase component with water inside the reactor. Step (4): a step for discharging, as a liquid phase component inside the reactor, the reaction liquid containing the compound of general formula (III) to the outside of the reactor.

Organic amine collection method

A method is provided for collecting a compound of formula (III) (in which R31 is a monovalent to trivalent organic group and n31 is an integer of 1 to 3) from a liquid phase component that is formed as a by-product in a method for producing a compound of general formula (I) (in which R11 is a monovalent to trivalent organic group and n 11 is an integer of 1 to 3), wherein the collection method contains steps (1) to (3) or steps (A) and (B), and step (4). Step (1): a step for reacting the liquid phase component with at least one active hydrogen-containing compound in a reactor. Step (2): a step for returning a condensed liquid obtained by cooling gas phase components in the reactor to the reactor. Step (3): a step for discharging gas phase components that are not condensed in the step (2) to the outside of the reactor. Step (A): a step for mixing the liquid phase component, water, and a compound of general formula (III). Step (B): a step for reacting the liquid phase component with water inside the reactor. Step (4): a step for discharging, as a liquid phase component inside the reactor, the reaction liquid containing the compound of general formula (III) to the outside of the reactor.RNCO)&#x2003;&#x2003;(I)RNH)&#x2003;&#x2003;(III)

An isocyanate production method according to the present invention is a method in which an isocyanate is produced by subjecting a carbamate to thermal decomposition, and includes: a step of preparing a mixture liquid containing the carbamate, an inactive solvent and a polyisocyanate compound; a step of conducting a thermal decomposition reaction of the carbamate by continuously introducing the mixture liquid into a thermal decomposition reactor; a step of collecting a low-boiling decomposition product by continuously extracting the low-boiling decomposition product in a gaseous state from the reactor, the low-boiling decomposition product having a boiling point lower than the polyisocyanate compound; and a step of collecting a high-boiling component by continuously extracting, from the reactor, a liquid phase component which is not collected in a gaseous state at the step of collecting the low-boiling decomposition product.

Isocyanate production method

The present invention relates to a reaction method comprising a step of supplying a liquid containing at least one raw material compound and a low-boiling compound having a standard boiling point lower than a standard boiling point of the raw material compound to a flow channel, a step of heating the liquid to produce a liquid reaction product and a gas component by a reaction of the raw material compound, and a step of separating a liquid phase containing the reaction product from a gas phase containing the gas component and the low-boiling compound.

Growing community of inventors

Tokyo, Japan

Takeharu Sasaki