| abstract |
A new process for working up aqueous amine solutions, such as those obtained in the catalytic hydrogenation of aromatic dinitro compounds, by separating off the water by distillation together with the steam-volatile organic by-products in a distillation column, the vapors of the distillation column being condensed, the liquid phase obtained in this way using a separating apparatus leads in which vapor-volatile, organic by-products are removed from the vapor condensate as organic phase, which returns the aqueous phase leaving the separating apparatus to the top of the distillation column, removes the water largely freed from steam-contaminated organic impurities via a side stream and removes the water and steam-volatile from the distillation column Contaminants largely free diamines as a bottom product. |