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:
Oct. 22, 2013
Filed:
Jun. 26, 2010
Rainer Bruns, Leverkusen, DE;
Wolfgang Lorenz, Dormagen, DE;
Friedhelm Steffens, Leverkusen, DE;
Herbert Stutz, Dormagen, DE;
Rainer Bruns, Leverkusen, DE;
Wolfgang Lorenz, Dormagen, DE;
Friedhelm Steffens, Leverkusen, DE;
Herbert Stutz, Dormagen, DE;
Bayer MaterialScience AG, Leverkusen, DE;
Abstract
An isocyanate is produced by reacting an amine with a stoichiometric excess of phosgene in the gas phase. This reaction is carried out at a temperature above the amine's boiling point to obtain a liquid stream containing the isocyanate and a gas stream containing hydrogen chloride and phosgene. The gas stream containing hydrogen chloride and phosgene thus produced is separated into a gas stream containing hydrogen chloride and a liquid stream containing phosgene. At least part of the liquid stream containing phosgene is then converted to a gas stream containing phosgene which gas stream is then recycled. The gaseous phosgene stream is maintained at a higher pressure than the liquid phosgene stream.