| Formamide, a sort of polar solvent with a high boiling point has water white transparency and is tasteless, it has great dissolving capacity and active reactivity. Formamide is widely used at fields of organic synthesis, medicine manufacturing, perfumery and dyestuff chemistry, etc. Currently, the technique of synthesis at gas-phase under atmosphere we take domestically has kinds of shortages. Most high-purity form amid we need is imported, and the requirement increases greatly. Therefore, the study of high-efficiency manufacturing technique of high-purity of form amid has become to the main project.In this paper,we synthesis formamide under liquid phase condition,and made qualitative and quantitative analysis. With MF and liquid ammonia as raw materials and catalyst, it turned out that the reaction goes on, causing no side reaction, so only methanol is byproduct. During this reaction, methanol behaves as catalysts and initiators. The result shows liquid phase reaction give a significant lead over gas-phase reaction, which has smaller reactor volume, lower cost of the investment, faster reaction rate, smaller raw material loss and higher product yield. Particularly, the conversion increased 4.96%.After initially purified by simple distillation, the form amide products purity can reach 93.9%. Then, through vacuum distillation under the conditions, vacuum 0.08-0.09MPa, temperature 20-90℃, the Formamide content can be effectively increased to 96.6%.The effects to the reactive procedure of temperature, pressure , time and catalyst have been measured. The result shows that Temperature has little effect on the reaction, while a lower pressure and effective catalyst promotes the reaction obviously. At the beginning, the reaction speed has nothing to do with MF concentration, however, when MF conversion is above 96%, the process slows down immediately. Under the condition: top temperature 42℃, pressure 0.62MPa, time 40min, catalyst15g, the reaction conversion is 98.73%.
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