Process for preparing isocyanates

摘要

The invention relates to a process for preparing isocyanates by reacting the corresponding amines with phosgene in the gas phase, if appropriate in the presence of an inert medium, in which the amine and the phosgene are first mixed and converted to the isocyanate in a reactor, by cooling a reaction gas which comprises isocyanate and hydrogen chloride and leaves the reactor in a quench by adding a liquid quench medium to obtain a mixture of reaction gas and quench medium. The amount of quench medium added is such that the temperature of the mixture of reaction gas and quench medium which is established in the quench is above the dew point of the gas present in the quench.

主权项

1. A process for preparing isocyanates, comprising:
mixing an amine and phosgene in a reactor; reacting the amine with phosgene in the gas phase, optionally in the presence of an inert medium, thereby forming a reaction gas that comprises an isocyanate and hydrogen chloride; and contacting the reaction gas which comprises the isocyanate and hydrogen chloride with a liquid quench medium, thereby cooling the reaction gas and obtaining a mixture of the reaction gas and the quench medium, each in gaseous form, wherein the amount of quench medium added is such that the temperature of the mixture of reaction gas and quench medium which is established in the quench is above the dew point of the gas mixture present in the quench.