The Separation Of Hazardous Substances From Acid In Nitration Waste Liquid

In pharmaceuticals, explosives, dyes, defense and other areas, nitrotoluene compounds were widely used. Particularly in the industrial production of dinitrotoluene there were a large number of hazardous and harmful substances, such as nitro derivatives cresol (2,6-dinitro-p-cresol,4,6-dinitro-o-cresol,4,6-dinitro-o-cresol,2.4,6-trinitro-m-cresol) and other inflammable substances. In this paper, toluene as raw material, Sulfuric acid as catalyst, nitrate as nitrating agent, referring the industrial nitrification process of toluene, the toluene was nitrified. Then that the explosive and inflammable substances were separated from sulfonitric mixed acid after the nitration of nitrotoluene, dinitrotoluene and trinitrotoluene was studied.By adding oxidant and adsorbent, hazardous substances were effectively separated from wasted acid. The separated waste solution was applied by Fourier transform infrared spectroscopy and UV spectrophotometer to analyze and characterize. And determine that the best removal of impurity was the common action of oxidants and adsorbents. There was mainly ammonium sulfate in the solution after the separation, although containing small amounts of impurities. After the product purified by recrystallization, the purity of products was almost the same with analytical’s, up to about98%.Through these studies, preliminarily that the hazardous substances was separated from the mixed acid of the toluene nitration processes presented a green and effective way, lying the foundation for the safety handling of wasted acid and efficient use of resources.