Patent ID: 9376377
Filing Date: 2016-06-28
CPC Classification: C07C

Claim Text:
1. A method for producing an isocyanate by reacting the corresponding primary amine with phosgene in a reactor which comprises at least one reaction zone and a quenching zone arranged below the reaction zone, comprising: (i) introducing a gaseous amine stream and a gaseous phosgene stream into the reactor and reacting the mixture in the reaction zone to form a product gas stream comprising isocyanate and hydrogen chloride; (ii) introducing the product gas stream into the quenching zone in which the product gas stream is cooled by spraying in a quench liquid via at least one quench nozzle in such a manner that a liquid stream comprising quench liquid and isocyanate is obtained; and (iii) isolating the isocyanate from the liquid stream obtained in step (ii); wherein the temperature of the wall of the reaction zone immediately above the quenching zone is maintained at a value which is at most 15% below the maximum temperature in Kelvin of the wall of the reaction zone.