TREATMENT OF 2,4-DINITROTOLUENE USING A 2-STAGE SYSTEM - FLUIDIZED-BED ANAEROBIC GRANULAR ACTIVATED CARBON REACTORS AND AEROBIC ACTIVATED-SLUDGE REACTORS

Continuous-flow anaerobic fluidized-bed granular activated carbon bior eactors were used to treat 2,4-dinitrotoluene (2,4-DNT), a compound us ed in primary propellant production. A synthetic wastewater solution c ontaining 2,4-DNT, ethanol, mineral ether, and a carbonate buffer and another solution containing growth nutrients and vitamins were fed to each of the two bioreactors. The influent ethanol concentrations were varied to determine the effect of ethanol concentration on the extent of 2,4-DNT degradation. The anaerobic bioreactors, when operated under methanogenic conditions with a primary substrate, were able to transf orm the 2,4-DNT into 2-amino-4-nitrotoluene (2-A-4-NT), 4-amino-2-nitr otoluene (4-A-2-NT), 2,4-diaminotoluene (2,4-DAT), and trace amounts o ftoluene. During stable operation, for the range of non-zero influent ethanol concentrations evaluated in this study, the majority of the pr oducts were identified as 2,4-DAT. Batch activated sludge reactors wer e used to examine the fate of 2,4-DAT under aerobic conditions. 2,4-DA T (16 mg/L) were mineralized within 9 hours, indicating that a two-sta ge system may be an effective 2,4-DNT treatment strategy.