METODO PER LA PREPARAZIONE DI PARACLOROFENILENDIAMMINA

摘要

1417662 p-Chloro-m-phenylenedia mine preparation GOODYEAR TIRE & RUBBER CO 11 June 1974 [2 July 1973] 25822/74 Heading C2C A method of preparing p-chloro-m-phenylenediamine comprises hydrogenating 4-chloro-1,3- dinitro benzene in a solvent solution which will dissolve said diamine and which comprises from 85 to 100 weight per cent of an ester and from 0 to 15 weight per cent of a mono alcohol at a pressure in the range of from 400 to 1000 pounds per square inch gauge and at a temperature in the range of from 60‹ to 140‹ C. in the presence of a reduced platinum on granular carbon catalyst which comprises from 0À5 to 1À5 weight per cent platinum which catalyst is characterized by having a nitrobenzene number (as hereinafter defined) in the range of 260 to 3200 and further characterized by the platinum being reduced on the carbon support by at least 95% and means being provided for the introduction of the hydrogen which preferably comprises a dispersive hydrogen charging means positioned beneath the liquid mixture. The nitrobenzene number is calculated as the volume of hydrogen at STP taken up over the first five minutes of reaction per gram of dry catalyst.