PROCESS FOR THE SEPARATION BY DISTILLATION OF DINITROTOLUENE FROM PROCESS WASTEWATER FROM THE PREPARATION OF DINITROTOLUENE BY NITRATION OF TOLUENE BY MEANS OF NITRATING ACID

摘要

A process is proposed for distillatively removing dinitrotoluene from process wastewater from the preparation of dinitrotoluene by nitrating toluene with nitrating acid, which comprises basifying the process wastewater to a pH of 8.5, feeding it to a stripping column in the upper region thereof and stripping it with steam in countercurrent to obtain a vapor stream laden with dinitrotoluene and a bottom stream depleted in dinitrotoluene compared to the process wastewater used.