Mineralization of dinitrotoluenes and trinitrotoluene of spent acid in toluene nitration process by Fenton oxidation.
Fenton's reagent, UV/H2O2 and UV/Fenton's reagent were employed to mineralize dinitrotoluene (DNT) isomers and 2,4,6-trinitrotoluene (TNT) of spent acid in toluene nitration process. The bench-scale experiments were conducted to elucidate the influence of various operating variables on the performance of removal of total organic compounds (TOC) from spent acid, including reaction temperature, concentration of ferrous ion and H2O2 dosage. It is remarkable that organic compounds were completely mineralized by Fenton oxidation, of which removal efficiency is superior to that of UV/H2O2. Nevertheless, it makes slight difference between Fenton oxidation and UV/Fenton oxidation. According to the spectra identified by gas chromatograph/mass spectrometer (GC/MS), it is proposed that oxidative degradation of DNT isomers leads to o-, m-, p-mononitrotoluene (MNT) and 1,3-dinitrobenzene respectively. Besides, the oxidation of 2,4,6-TNT gives the 1,3,5-trinitrobenzene intermediate. Apparently, Fenton oxidation is promising for purification of spent acid industrially.
Chen
Wen-Shing
WS
Department of Chemical Engineering, National Yunlin University of Science and Technology, 123 University Road, Yunlin 640, Taiwan, ROC. chenwen@yuntech.edu.tw
Juan
Chien-Neng
CN
Wei
Kuo-Ming
KM
D004136:Dinitrobenzenes / Q000032:analysis / Q000737:chemistry* / Q000528:radiation effects; D005296:Ferrous Compounds / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000737:chemistry*; D007220:Industrial Waste; D007501:Iron / Q000737:chemistry*; D010084:Oxidation-Reduction; D014050:Toluene / Q000737:chemistry*; D014303:Trinitrotoluene / Q000032:analysis / Q000737:chemistry* / Q000528:radiation effects; D014466:Ultraviolet Rays; D014865:Waste Disposal, Fluid / Q000379:methods
D004136:Dinitrobenzenes; C045076:Fenton's reagent; D005296:Ferrous Compounds; D007220:Industrial Waste; D014303:Trinitrotoluene; C020748:ferrous sulfate; D014050:Toluene; D006861:Hydrogen Peroxide; D007501:Iron