| abstract |
Process for the phosgenation of monocarboxylic acids and/or anhydrides, characterized in that the acid and/or the anhydride is treated, in the presence or absence of solvent, with a molar excess of phosgene, preferably 2 to 15 times as much phosgene as acid, at temperatures between 80 and 200{C and at pressures between 2 and 60 bar, with or without catalyst, preferably in the absence of any catalyst. Process furthermore characterized in that pressure is used to facilitate the separation of the hydrochloric acid, the carbon dioxide and the phosgene, in a column which is external to the reactor. |