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:
Jan. 04, 2022
Filed:
Sep. 03, 2018
Applicant:
Covestro Deutschland Ag, Leverkusen, DE;
Inventors:
Dirk Manzel, Moers, DE;
Peter Plathen, Krefeld, DE;
Peter Wolf, Duisburg, DE;
Udo Boegel, Duisburg, DE;
Assignee:
Covestro Deutschland AG, Leverkusen, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B08B 9/032 (2006.01); B08B 5/00 (2006.01); C11D 7/04 (2006.01); C11D 11/00 (2006.01); C01B 32/80 (2017.01); B01D 53/02 (2006.01); B01J 19/00 (2006.01);
U.S. Cl.
CPC ...
B08B 9/0328 (2013.01); B01D 53/02 (2013.01); B01J 19/0006 (2013.01); B08B 5/00 (2013.01); C01B 32/80 (2017.08); C11D 11/0041 (2013.01); B01D 2253/102 (2013.01); B01D 2259/40084 (2013.01); B01J 2219/00247 (2013.01);
Abstract
The invention relates to a method for cleaning a phosgene conducting apparatus, comprising: washing the apparatus with hot inert gas, followed by washing the apparatus with cold inert gas; conveying gaseous ammonia for breaking down phosgene residues with a continuous increase in temperature until a maximum temperature ranging between 30° C. to 120° C. is reached; once the maximum temperature is reached, shutting down the ammonia supply and the conveying of inert gas, optionally followed by washing the apparatus with an aqueous stream.