METHOD AND DEVICE FOR PRODUCING PHOSGENE Russian patent published in 2010 - IPC C01B31/28 B01J7/00 B01J8/06 

FIELD: chemistry.

SUBSTANCE: invention relates to technology of producing phosgene. Phosgene is obtained by reacting chlorine and carbon monoxide in the presence of activated carbon as a catalyst in a shell-and-tube reactor having several reaction tubes and cooling space around said tubes, wherein the reaction tubes are subjected to external evaporation cooling by the cooling space with water and are used under pressure which is higher than pressure of the cooling space. Carbon monoxide is used in molar excess with respect to the amount of chlorine used, which is between 2 and 20 %, and absolute pressure in the cooling space is between 0.1 and 0.8 bars. The invention also describes a device for producing phosgene, consisting of a shell-and-tube reactor 20, 30, comprising several parallel reaction tubes 21, 61, surrounded by cooling space 27, 67 for water with at least one inlet opening 13, 53 for water and at least one outlet opening 14, 54 for water and water vapour, as well as a water circulation loop 26, 66, which includes a separator 22, 62 for separating water and water vapour, hydraulically connected by a pipe 6, 46 with an outlet opening 14, 54, a recirculation pipe 5, 45 designed for returning water separated in the separator 22, 62 to the inlet opening 13, 53, a heat exchanger 23, 63 which is hydraulically connected by a steam pipe 7, 47 to the separator 22, 62 and in which water vapour separated in the separator 22, 62 condenses, as well as a recirculation pipe 8, 48 designed for returning water condensed in the heat exchanger 23, 63 to the inlet opening 13, 53. The device also has a vacuum line 9, 49 which is hydraulically connected to the separator 22, 62 for separating water and water vapour through the steam pipe 7, 47 and/or heat exchanger 23, 63 and which can be connected to a vacuum generating device, wherein the vacuum line 9, 49 can be air-tightly closed, as well as at least one monitoring device 24, 25, 64, 65 located in the water circulation loop 26, 66 or cooling space 27, 67, through which penetration of phosgene into the water circulation loop 26, 66 or cooling space 27, 67 can be monitored.

EFFECT: invention enables to keep gas temperature at the output of the reactor lower than 100°C due to efficient heat removal, and concentration of chlorine in phosgene less than 50 parts per million and simultaneously ensure reliable operation of the reactor.

5 cl, 3 dwg