PROCESS FOR THE SEPARATION BY DISTILLATION OF DINITROTOLUENE FROM PROCESS FOR THE SEPARATION BY DISTILLATION OF DINITROTOLUENE FROM 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.