S131 Sequencing batch reactor for biotransformation of 2,4-dinitroanisole (DNAN) and 3-nitro-1,2,4-triazol-5-one (NTO)
Wednesday, July 27, 2016: 10:00 AM
Grand Couteau, 5th Fl (Sheraton New Orleans)
J. Weidhaas*, A. Panaccione, A. Anderson and S. Poudel Acharya, West Virginia University, Morgantown, WV
Defense agencies are increasingly using insensitive munitions (IMs) in place of traditional explosives such as trinitrotoluene. In this study biotransformation of the IM formulation constituents 2,4-dinitroanisole (DNAN) and 3-nitro-1,2,4-triazol-5-one (NTO) were evaluated in oxic and anoxic sequencing batch reactors (SBRs). The oxic SBRs were fed minima media supplemented with 20.5 +/- 5.9 mg/L DNAN (average +/- standard deviation) and 9.5 +/- 6.6 mg/L NTO as the nitrogen source. The oxic SBRs were supplemented with 10% LB media during 4 cycles. The oxic SBR was operated over 6 months and 26 cycles. Between 52+/- 17 and 42+/-19 % of DNAN and NTO respectively were removed in the oxic SBR. However when LB media was also present in the reactor DNAN and NTO removal increased to 79 +/- 11 and 53 +/- 27 %, respectively. In total 52 +/- 26 percent of COD was degraded in the oxic SBR. The anoxic SBR was operated over 3 months and 12 cycles. The anoxic SBR was fed LB media supplemented with 18 +/- 6 mg/L DNAN and 11 +/- 4 mg/L NTO. Both DNAN and NTO were completely transformed in the anaerobic reactors within 4 hours to 2 days, respectively. In the anoxic SBR, an average of 35 +/- 15 % of COD was degraded during operation. Degradation products monitored in both reactors included nitrate, dinitrophenol and 5-amino-1,2,4-triazol-3-one. Metatranscriptomics was conducted on the anoxic SBR to identify genes upregulated during DNAN and NTO degradation compared to degradation of LB media.