Stduy On The Removal Of Nitrotoluene Compounds From Concentrated Waste Acid

Nitrotoluene compounds were widely used in the production of pharmaceuticals, explosives,dyes and other chemical products.However, High concentrated waste acid contained nitrotoluene compounds and a very complex composition, they were toxic and difficult to deal with. The method proposed by this paper has a lot of characterisitics such as green, simple and easy to be extracted, can be recycled and industrialization. It has showed a good removal rate to direct proposed the high concentrated waste acid. The recovered pure concentrated waste acid can be used in other chemical process, it has provided a new way of thinking of the utilization of waste acid and has extremely important economic significance and social benefits.In the paper we based on the characteristics of the perfluorochernicals and the advantage of fluorous biphasic system(FBS),find out that some perfluorinated solvents (Perfluorodecalin, Perfluorotoluene, Perfluorobenzene,etc) were suitable for dealing with high concentrated waste acid directly and has showed the better remove ability to the nitrotoluene compounds.In the experiment we used perfluorinated toluene to extraction the waste acid three times, there was no detection for nitrotoluene compounds in waste acid, the removal rate reached100%. We used perfluorodecalin to extract the waste acid three times, the MNT removal rate was99.3%, the DNT removal rate was65.5%.We also designed experiments to study the optimum conditions of the extraction, such as extraction time,extraction temperature,phase ratio and so on. The works have laid the foundation for the industrialization of the high concentrated waste acid processing.According to the shortcomings and deficiencies of perfluorodecalin, we designed a series of polyfluoro-compound containing a specific structure as an efficient perfluoro extractant, to assist perfluorodecalin to remove dinitrotoluene compounds, improved the extraction effect. We synthesized such as N, N-bis(1,1,2,2-tetrahydro-perfluoroalkyl)-1,3-phenylenediamine,1,2,4,5-tetrafluoro-3-((3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)oxy)-6-(trifluoromethyl)ben-zene by perfluoro-alkylation reaction. They all have showed a good removal rate. Such as the compound1,2,4,5-tetrafluoro-3-((3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)oxy)-6-(trifl-uoromethyl)benzene, extracted the waste acid three times, the MNT removal rate was100%, the DNT removal rate was98.45%.With exploration the condition and parameters of the reaction, the optimized parameters are achieved.