Replacing phosgene with sodium cyanate laid a solid foundation for the promotion of green technology
Phosgene is widely used in the preparation of polyurethane, polycarbonate and urea plastics. However, due to the highly toxic nature of phosgene, from the perspective of green chemistry, sodium cyanate is a safe and appropriate alternative to phosgene green products.
With the continuous improvement of safety standards in the production process of chemical industry and the emergence of process safety and clean production technology, the production process still using phosgene and solid phosgene will gradually be replaced by sodium cyanate, mainly in the field of medicine and pesticide.
The application of sodium cyanate instead of phosgene in the synthesis of pesticide and medicine has the advantages of high safety, high yield and quality, and less three wastes. Phosgene is a very dangerous chemical gas, which has been banned or restricted in many countries. In particular, phosgene is not easy to transport and store, and is only used in the plant. And using phosgene as raw material, it is difficult to measure accurately, the safety of operation is poor, its use and storage is very dangerous, and it is difficult to control the leakage of phosgene, which is very harmful.
With the advent of the era of green chemistry, it is urgent to find a clean production way to replace phosgene. Since the 1980s, scientists have been trying to explore the green chemical technology to replace phosgene. The corresponding pesticides were synthesized by using phosgene, solid phosgene and oxalyl chloride instead of phosgene. These methods have their own advantages and disadvantages. In these technologies, the phosgene is replaced by diphosgene and solid phosgene. In addition to the higher price than phosgene, both diphosgene and solid phosgene will produce phosgene in the reaction process. There is always the possibility of phosgene leakage and high production risk. The irritant odor and strong tear - inducing property of oxalyl chloride are not acceptable in industrial production.
The use of sodium cyanate instead of phosgene in pesticide synthesis is a promising green production process. Especially in recent years, through continuous process improvement, the quality of sodium cyanate has been rising steadily and the cost has been falling, which has laid a solid foundation for the promotion of this green process.
With the continuous improvement of safety standards in the production process of chemical industry and the emergence of process safety and clean production technology, the production process still using phosgene and solid phosgene will gradually be replaced by sodium cyanate, mainly in the field of medicine and pesticide.
The application of sodium cyanate instead of phosgene in the synthesis of pesticide and medicine has the advantages of high safety, high yield and quality, and less three wastes. Phosgene is a very dangerous chemical gas, which has been banned or restricted in many countries. In particular, phosgene is not easy to transport and store, and is only used in the plant. And using phosgene as raw material, it is difficult to measure accurately, the safety of operation is poor, its use and storage is very dangerous, and it is difficult to control the leakage of phosgene, which is very harmful.
With the advent of the era of green chemistry, it is urgent to find a clean production way to replace phosgene. Since the 1980s, scientists have been trying to explore the green chemical technology to replace phosgene. The corresponding pesticides were synthesized by using phosgene, solid phosgene and oxalyl chloride instead of phosgene. These methods have their own advantages and disadvantages. In these technologies, the phosgene is replaced by diphosgene and solid phosgene. In addition to the higher price than phosgene, both diphosgene and solid phosgene will produce phosgene in the reaction process. There is always the possibility of phosgene leakage and high production risk. The irritant odor and strong tear - inducing property of oxalyl chloride are not acceptable in industrial production.
The use of sodium cyanate instead of phosgene in pesticide synthesis is a promising green production process. Especially in recent years, through continuous process improvement, the quality of sodium cyanate has been rising steadily and the cost has been falling, which has laid a solid foundation for the promotion of this green process.
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