Process for purifying wastewaters from the workup of crude aromatic nitro compounds

摘要

The invention relates to a process for purifying crude aromatic nitro compounds which originate from the nitration of aromatic compounds, comprising the single or multiple performance of the following wash stage (a): (a) contacting the crude aromatic nitro compound (N-in) with an aqueous phase (W-res) and then separating the phases to obtain an organic phase (N-res) and an aqueous phase (W-res), wherein at least one demulsifier (D) is present in one or more of the wash stages (a).