A process for the production of high-quality aniline from mononitrobenzene.
Aniline is produced by the nitration of benzene with nitric acid to mononitrobenzene (MNB) which is subsequently hydrogenated to aniline. In the DuPont process, purified MNB is fed, together with hydrogen, into a liquid phase plug-flow hydrogenation reactor that contains a DuPont proprietary catalyst. The supported noble metal catalyst has a high selectivity and the MNB conversion per pass is 100%. The reaction conditions are optimized to achieve essentially quantitative yields and the reactor effluent is MNB-free. The reactor product is sent to a dehydration column to remove the water of reaction followed by a purification column to produce high-quality aniline product.
Product quality: The DuPont aniline process consistently produces a very high quality aniline product, suitable for all MDI production technologies, and other specialty chemical applications. The typical product quality is:
Aniline, wt% 99.95
MNB, ppmwt 0.1
Water, ppmwt 300
Color, APHA 30
Freeze point (dry basis), °C –6.0
Licensor: Kellogg Brown & Root LLC