| 摘要 |
1. Method for preparing melamine from urea via a high-pressure process in which solid melamine is obtained by transferring the reactor product comprising liquid melamine, CO2 and NH3 to a gas/liquid separator and subsequently transferring the melamine melt coming from the separator to a vessel where the melamine melt is cooled with an evaporating cooling medium, characterized in that, the gas/liquid separation is conducted by addition of 5x10<-4>- 2x10<-2> mole of water per mole of melamine. 2. Method according to claim 1, characterized in that, 10<-3> - 10<-2> mole of water per mole of melamine is added. 3. Method according to any one of claims 1-2, characterized in that, the gas-liquid separation is conducted by addition of 0.01-10 mole of ammonia per mole of melamine. 4. Method according to claim 3, characterized in that, the gas-liquid separation is conducted by addition of 0.1-5 mole of ammonia per mole of melamine.
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