公开(公告)号：US3598818A

公开(公告)日：1971-08-10

申请号：US3598818D

申请日：1969-11-17

Applicant: STAMICARBON

Inventor： KREKELS JACOBUS T C

IPC: C07D251/60 ,  H01R39/36 ,  C07D55/24

CPC classification number: C07D251/60 ,  H01R39/36

Abstract: A PROCESS IS DISCLOSED FOR THE SEPARATION AND RECOVERY OF MELAMINE FROM GASEOUS MIXTURES OF MELAMINE, AMMONIA AND CARBON DIOXIDE OBTAINED IN THE MANUFACTURE OF MELAMINE FROM UREA AND UNDER SUPERATMOPHERIC PRESSURE. THE PROCESS INVOLVES FEEDING A DILUTE SUSPENSION OF MELAMINE CRYSTALS IN A SOLUTION SATURATED WITH AMMONIUM AND CARBON DIOXIDE INTO AT LEAST ONE HYDROCYCLONE AND OBTAINING BY SEPARATION THEREIN (A) A CONCENTRATED AQUEOUS MELAMINE SOLUTION AND (B) A DILUTE MELAMINE SOLUTION; AND RECIRCULATING THIS DILUTE MELAMINE SOLUTION CONTAINING MOST OF THE AMMONIA AND CARBON DIOXIDE COMPONENTS OF THE AFORESAID GASEOUS MIXTURE, TO THE INITIAL COOLING ZONE WHEREIN MELAMINE CRYSTALS ARE FIRST OBTAINED IN THE FORM OF A SUSPENSION IN AN AQUEOUS SOLUTION CONTAINING AMMONIA AND CARBON DIOXIDE.