GB1218522A - A process for recovering the purified melamine - Google Patents

A process for recovering the purified melamine

Info

Publication number
GB1218522A
GB1218522A GB430169A GB430169A GB1218522A GB 1218522 A GB1218522 A GB 1218522A GB 430169 A GB430169 A GB 430169A GB 430169 A GB430169 A GB 430169A GB 1218522 A GB1218522 A GB 1218522A
Authority
GB
United Kingdom
Prior art keywords
melamine
pressure
purified
cooling
ammonia
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB430169A
Inventor
Ryo Kokubo
Koji Yokomichi
Yasuo Takakuwa
Mizuhiko Nagakura
Isao Maruyama
Akihiro Shiroishi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nissan Chemical Corp
Original Assignee
Nissan Chemical Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nissan Chemical Corp filed Critical Nissan Chemical Corp
Priority to GB430169A priority Critical patent/GB1218522A/en
Publication of GB1218522A publication Critical patent/GB1218522A/en
Expired legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D251/00—Heterocyclic compounds containing 1,3,5-triazine rings
    • C07D251/02—Heterocyclic compounds containing 1,3,5-triazine rings not condensed with other rings
    • C07D251/12—Heterocyclic compounds containing 1,3,5-triazine rings not condensed with other rings having three double bonds between ring members or between ring members and non-ring members
    • C07D251/26—Heterocyclic compounds containing 1,3,5-triazine rings not condensed with other rings having three double bonds between ring members or between ring members and non-ring members with only hetero atoms directly attached to ring carbon atoms
    • C07D251/40—Nitrogen atoms
    • C07D251/54—Three nitrogen atoms
    • C07D251/62—Purification of melamine

Abstract

1,218,522. Purification of melamine. NISSAN KAGAKU KOGYO K.K. 24 Jan., 1969, No. 4301/69. Heading C2C. Purified melamine is prepared from the crude melamine obtained from the thermal decomposition of urea by solidifying the molten crude melamine by cooling it from 5 to 100 Kg./sq. cm. pressure to 270‹ to 200‹ C. with atomized liquid ammonia or a cool ammonia gas, cooling the solidified melamine to from 100‹ to 200‹ C. with an aqueous solution containing from 5 to 80%, preferably 20 to 50%, of ammonia which also serves to dissolve the melamine and to remove the impurities, and crystallizing the purified melamine from the melamine solution. The melamine is preferably crystallized firstly at a pressure of 1 to 15 Kg./sq. cm. to allow recovery of dissolved gases and secondly at a pressure of 30 to 70 mm. Hg absolute and at a temperature of 20‹ to 60‹ C.
GB430169A 1969-01-24 1969-01-24 A process for recovering the purified melamine Expired GB1218522A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB430169A GB1218522A (en) 1969-01-24 1969-01-24 A process for recovering the purified melamine

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB430169A GB1218522A (en) 1969-01-24 1969-01-24 A process for recovering the purified melamine

Publications (1)

Publication Number Publication Date
GB1218522A true GB1218522A (en) 1971-01-06

Family

ID=9774586

Family Applications (1)

Application Number Title Priority Date Filing Date
GB430169A Expired GB1218522A (en) 1969-01-24 1969-01-24 A process for recovering the purified melamine

Country Status (1)

Country Link
GB (1) GB1218522A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2557876A1 (en) * 1984-01-05 1985-07-12 Melamine Chemicals Inc HIGH PRESSURE SYNTHESIS OF ANHYDROUS MELAMINE
DE3500188A1 (en) * 1984-01-05 1985-07-18 Melamine Chemicals, Inc., Donaldsonville, La. Continuous prodn. of high purity melamine from urea
DE3546893C2 (en) * 1984-01-05 1995-10-26 Melamine Chemicals Inc Continuous prodn. of high purity melamine from urea

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2557876A1 (en) * 1984-01-05 1985-07-12 Melamine Chemicals Inc HIGH PRESSURE SYNTHESIS OF ANHYDROUS MELAMINE
DE3500188A1 (en) * 1984-01-05 1985-07-18 Melamine Chemicals, Inc., Donaldsonville, La. Continuous prodn. of high purity melamine from urea
GB2152505A (en) * 1984-01-05 1985-08-07 Melamine Chemicals Inc Production of melamine
DE3546893C2 (en) * 1984-01-05 1995-10-26 Melamine Chemicals Inc Continuous prodn. of high purity melamine from urea
DE3546893C3 (en) * 1984-01-05 1998-01-29 Melamine Chemicals Inc Anhydrous high-pressure melamine synthesis

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