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:
Dec. 05, 2023
Filed:
Jul. 06, 2021
Casale SA, Lugano, CH;
Andrea Scotto, Breganzona, CH;
Simone Gamba, Pagazzano, IT;
Casale SA, Lugano, CH;
Abstract
A process for the purification of a melamine melt () containing melamine and by-products, comprising the steps of: (a1) In quenching of said melamine melt; (a2) decomposition of by-products with alkali, providing an alkaline aqueous solution of melamine (); (b) stripping of said alkaline aqueous solution of melamine (); (c) crystallization of melamine with a first alkali-containing solution () and separation of solid melamine () from a mother liquor (); (d) treatment of said mother liquor, providing a waste water stream () containing carbonates; (e) decomposition of at least part of the carbonates contained in said waste water stream () into carbon dioxide and alkali, providing a second alkali-containing aqueous solution (); (f) recycle of at least part of said alkali-containing aqueous solution () to at least one of said steps (a1), (a2) and (c).