The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 18, 2025
Filed:
May. 12, 2021
Covestro Deutschland Ag, Leverkusen, DE;
Dietmar Wastian, Dormagen, DE;
Anke Hielscher, Cologne, DE;
Juergen Spriewald, Cologne, DE;
Achim Wildermuth, Neuss, DE;
Covestro Deutschland AG, Leverkusen, DE;
Abstract
The present invention relates to a method for operating a plant for continuous production of an isocyanate by converting a primary amine A with phosgene P whilst maintaining, based on the amino groups of the primary amine, a stoichiometric excess of phosgene in the presence of a solvent L in the liquid phase, using a first, adiabatically operated reaction chamber and a second, isothermally operated reaction chamber. The method is characterised in that a combination of measures, in particular the maintenance of a sufficiently high starting pressure and a sufficiently high starting temperature, is applied in order to bring the plant back into the target state, standard operation, starting from a state of interruption to production.