METHOD FOR PRODUCING ISOCYANATES IN THE GAS PHASE

摘要

The invention relates to a process for the preparation of isocyanates by reaction of the corresponding amines with phosgene in the gas phase, wherein a diluent containing between 90.0000% by weight and 99.9999% by weight of substances which are inert in the phosgenation process and between 0.0001% by weight and 10.0000% by weight of oxygen is present during the conversion of the amine into the gas phase and the molar ratio of amine to oxygen (O2) is ≧1,000:1.

主权项

1. Process for the preparation of isocyanates by reaction of the corresponding amines with phosgene in the gas phase, wherein
(i) the amine is converted into the gas phase in a vaporization space in the presence of from >0.10% by weight to 25% by weight of a diluent, based on the total weight of diluent and amine; (ii) the gaseous stream obtained from (i) containing amine and diluent is reacted with a gaseous phosgene stream in a reaction space to give the corresponding isocyanate; characterized in that
the diluent employed in step (i) contains between 90.0000% by weight and 99.9999% by weight of substances which are inert in the phosgenation process and between 0.0001% by weight and 10.0000% by weight of oxygen, in each case based on the weight of the diluent, and the molar ratio of amine to oxygen (O2) in step (i) in the vaporization space is ≧1,000:1.