US 7,547,801 B2 · Process for the continuous preparation of isocyanates

Process for the continuous preparation of isocyanates

AssigneeBayer MaterialScience AG

InventorsFritz Pohl, Ricardo Serra, Matthias Ehlers, Jeffrey S. Bolton, Gary B. Solak, Kirk J. Bourgeois, Gregory L. McCullough, Amber R. Hicks, Richard G. Hillman, James E. Sager, Xiaoyan Wang, Spotswood Miller, Ralf Ochel, Sara DeLucia

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Abstract

Isocyanates are produced by reacting an organic amine with phosgene in process which includes at least three stages. The first stage is carried out in a dynamic mixer. The second stage is carried out in at least one reactor. The third stage is carried out in at least one material separating apparatus. The pressure in the reactor of the second stage must be greater than or equal to the pressure in the dynamic mixer. The pressure in the third stage material separating apparatus must be lower than the pressure in the second stage reactor.

Claims10

Dependent claims

A process for the preparation of isocyanate by the reaction of an organic amine with phosgene in at least three stages comprising:

a) a first stage conducted in a dynamic mixer,
b) a second stage conducted in at least one reactor, and
c) a third stage conducted in at least one material separating apparatus
in which (1) the second stage reactor pressure is greater than the first stage dynamic mixer pressure, and (2) the third stage material separating apparatus pressure is lower than the pressure in the reactor of the second stage.

1 more element

Dependencies are inferred from the claim text.