Patent ID: 8993803
Filing Date: 2015-03-31
Classification: C01B

Abstract:
1. A process for preparing phosgene, the process comprising: reacting a reactant feed stream obtained by combining and mixing a chlorine feed stream and a carbon monoxide feed stream, wherein the carbon monoxide is introduced in a stoichiometric excess over chlorine, in catalyst tubes filled with beds of activated carbon in a reactor comprising a bundle of catalyst tubes, to give a product gas mixture which is separated into a liquid, phosgene-comprising product stream and an offgas stream comprising carbon monoxide which is discharged via a pressure-regulating valve, wherein the reaction of the reactant feed stream in the reactor and the separation of the product gas mixture are carried out under a pressure in the range from 2.0 to 6.0 bar gauge, and wherein the excess of carbon monoxide in the reactant feed stream is regulated without directly measuring the concentration of the carbon monoxide in the carbon monoxide feed stream by