ANAEROBIC AEROBIC COMPOSTING OF 2,4,6-TRINITROTOLUENE-CONTAMINATED SOIL IN A REACTOR SYSTEM/

A compost mixture consisting of 50% 2,4,6-trinitrotoluene (TNT)-contam inated soil, 30% chopped sugar beet, and 20% straw was anaerobically p ercolated for 19 days with tap water. Thereafter, the water was draine d off, and the mixture was aerated for 58 days. The anoxic conditions led to the transformation of 90% of the TNT to monoaminodinitrotoluene s and diaminomononitrotoluenes. In addition to well-known reduction pr oducts, three substances with identical UV spectra were generated duri ng this phase. They were identified as 4-acetylamino-2-hydroxylamino-6 -nitrotoluene (4-N-AcOHANT), 4-formamido-2-amino-6-nitrotoluene (4-N-F AmANT), and 4-acetylamino-2-amino-6-nitrotoluene (4-N-AcANT). The firs t two metabolites were degraded under aerobic conditions by 100% and 9 9.6%, respectively, whereas the concentration of 4-N-AcANT increased d uring the first 15 days of the aeration. Thereafter, the compound was also degraded by 99.6%. In conclusion, an efficient TNT remediation sy stem is presented that led to the identification of three conjugated T NT metabolites.