Study On The New Preparation Technologies Of Cyanamide

The paper mainly studies the new preparation technologies of cyanamide. The paper reviews the preparation technologies of cyanamide in domestic and overseas. We analyze the advantage and disadvantage of all the technologies, and we design two new technologies: urea- cyanamide method and ammonia, carbon dioxide- cyanamide method.Urea-cyanamide method: With different catalyst, under the condition of some temperature and time, urea and ammonia manufacture cyanamide under normal pressure. This technology confirms atomic economical principle and it is low energy-consuming, small pollution and simple refining technology, so it is a technology with good social and economic benefit. The difficulty of urea-cyanamide method is the selection of catalyst and equipments which have high request.Ammonia and carbon dioxide-cyanamide method: Under the condition of some temperature and time, a mixture of ammonia and carbon dioxide gases in some mol ratio are passed into an elongated quartz reactor tube, packed for about one half its length at the center section with finely divided silica gel, an apparently catalytic reaction occurs, and the cyanamide is obtained in good yields. There are a lot of materials, and the materials are cheap It is small pollution and it improves the environment of manufacture. The disadvantage of ammonia and carbon dioxide- cyanamide method is the operation condition of this technology has very high request.Our team compares urea-cyanamide method with ammonia and carbon dioxide- cyanamide method, and then we get the conclusion: urea-cyanamide method is better than ammonia and carbon dioxide- cyanamide method.