| abstract |
The invention relates to a method for treating alkaline process waste water from the nitration of aromatic compounds to mono-, di- and trinitroaromatic compounds having a pH value of 7.5 to 13 or a mixture W having a pH value from 6 to 10 of alkaline process waste water and the aqueous destillate of the sulfuric acid concentration, comprising the steps of a) acidifying the alkaline process waste water or the mixture W by adding concentrated sulfuric acid, which originates from the treatment of the aqueous phase containing sulfuric acid that occurs during nitration, to a pH value below 2, wherein a mixture A is created from a separating organic phase and acidic aqueous phase, and b) extracting the mixture A using an aromatic extraction means. |