Patent ID: 11858903
Assignee: CASALE SA
Field: Organic fine chemistry (Chemistry)
Classification: CPC C | IPC C

Claim 0:
1. A process for the synthesis of melamine from urea, wherein offgas containing ammonia, carbon dioxide and melamine, which are formed during the synthesis of melamine, are quenched to recover the melamine contained therein,
wherein the quenching of the offgas comprises:
in a first portion of a quenching vessel, contacting an upward rising flow of said offgas in countercurrent with a descending flow of liquid ammonia, resulting in precipitation of solid melamine and formation of washed offgas with a reduced content of melamine or substantially melamine-free, which are withdrawn from said first portion of the vessel;
in a second portion of said vessel, which is below said first portion, contacting the precipitated solid melamine with a liquid solvent forming a solution of melamine or a melamine slurry, which is removed from the vessel.