公开(公告)号：GB1092762A

公开(公告)日：1967-11-29

申请号：GB1286565

申请日：1965-03-26

Applicant: BASF AG

Inventor： HAMPRECHT GUENTHER ,  FROMM HERMANN DIETER ,  SCHWARZMANN MATHIAS ,  ROTHER EBERHARD

IPC: C07D251/60

Abstract: Melamine is produced by heating urea and/or its thermal decomposition products at above 280 DEG C. in two stages in the presence of catalysts and ammonia or gases containing ammonia (e.g. recycled gas), the first stage comprising vaporizing the urea or decomposition product at 370 DEG -450 DEG C., and introducing the vapour and gas ito a second stage at 330 DEG -370 DEG C., the catalysts in the two stages being at least partly exchanged continuously or periodically. The second stage may consist of a plurality of zones; the catalysts may be fluidized. An example uses alumina as catalyst.