METHOD OF PRODUCING ISOCYANATE Russian patent published in 2013 - IPC C07C263/04 C07C263/18 C07C265/14 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing isocyanate via thermal decomposition of an ester of carbamic acid. The method involves the following steps: extracting a low-boiling point component in form of a gas-phase component from a chemical reactor for conducting thermal decomposition, wherein a thermal decomposition reaction is carried out; extracting a liquid-phase component containing an ester of carbamic acid from the bottom part of the chemical reactor for conducting thermal decomposition; and feeding all or a portion of the liquid-phase component into the top part of the chemical reactor for conducting thermal decomposition. The ester of carbamic acid is obtained by reacting an ester of carboni acid of formula (where R¹ denotes an aliphatic group containing 1-12 carbon atoms, or an aromatic group containing 6-12 carbon atoms) with an amino compound of formula (where R² is a group selected from a group consisting of an aliphatic group containing 1-20 carbon atoms, and an aromatic group containing 6-20 carbon atoms, wherein said group contains an atom selected from carbon and oxygen atoms and has valence equal to n, and n is an integer from 2 to 10).

EFFECT: method enables to obtain isocyanates over a long period of time, thus avoiding clogging of the chemical reactor caused by by-products sticking to reactor walls.

28 cl, 11 dwg, 1 tbl, 27 ex