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| Subject: Dicyandiamide Preparation Methods Thu Apr 15, 2010 3:38 pm | |
| Dicyandiamide or commonly 2-Cyanoguanidine is an amine derived from guanidine. It is a dimer of cyanamide, from which it can be prepared. 2-Cyanoguanidine is a colourless solid that is soluble in water, acetone, and alcohol, but not in diethyl ether or chloroform. It’s mainly used as a raw material for the manufacture of guan amine, gibuanide , various resins, trimetric cyan amide, fire retardant etc. Used as filler in leatherette and as additive in adhesive agent.
How to preparation Dicyandiamide ? Nitrogen lime (calcium cyanamide) with the water hydrolysis, will be suspended from the hydrolysis of ammonia liquid hydrogen cyanide filtering dehydroepiandrosterone calcium oxide, calcium liquid carbon dioxide-demineralized been cyanide, ammonia. Then, cyanide ammonia in alkaline conditions under polymerization. Generation DCD maximum speed of the temperature and pH : 50 ° C at pH 9.7; 80 ° C at pH 9.1; 100 ° C at pH 8.8. Control in these conditions after polymerization, and then cooling and crystallization, isolation, drying, dicyandiamide derived products. Industrial dicyandiamide content 99%, product consumption per ton of lime nitrogen (21% nitrogen) 4239kg. |
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