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:
Aug. 19, 2025
Filed:
Oct. 05, 2023
Casale SA, Lugano, CH;
Simone Gamba, Pagazzano, IT;
Casale SA, Lugano, CH;
Abstract
A process for the synthesis of melamine including the purification of the offgas released by the synthesis of melamine by means of a first purification stage followed by a second purification stage (); in the first purification stage () the offgas () is contacted with urea melt from the second stage () and with a recirculated urea melt () containing ammonia and melamine precursors (); in the second purification stage () the offgas from the first stage is contacted with fresh urea melt (); said recirculated urea melt is withdrawn from bottom of the first stage and cooled in a shell and tube heat exchanger () to a temperature of not less than 165° C. preferably in the range 165° C. to 245° C. prior to reintroduction in said first stage.