摘要 |
Mixtures containing aromatic nitro compounds and nitrophenols are separated by washing the mixture with water and passing it over a basic anion-exchange resin preferably in the presence of dilute aqueous sodium hydroxide solution, which retains the nitrophenols, while purified nitro compounds pass from the resin, separating the nitrophenols with simultaneous regeneration of the resin by treating the resins with a dilute mineral acid, preferably sulphuric acid, and an organic solvent preferably acetone, for nitrophenols. The resin may be a macroporous strongly basic anion exchanger based on a styrene/divinyl benzene copolymer containing quaternary ammonium groups. |