Accurate values of thermophysical properties of toxic chemical compounds over a range of temperatures are essential for understanding their environmental distribution, biotransformation, and development of potential water treatment processes. In this study, the aqueous solubility (s w), octanol–water partition coefficient (K ow), and Henry’s law constant (k H) were measured for an insensitive munitions compound, 2,4-dinitroanisole (DNAN), at the temperatures of (298.15, 308.15, and 318.15) K. The effect of ionic environment on solubility, using electrolytes such as NaCl and CaCl2, was also studied. The data on the thermophysical parameters were correlated using the standard van’t Hoff equation. All three properties exhibited a linear relationship with reciprocal temperature. The enthalpy and entropy of phase transfer were derived from the experimental data.

a b s t r a c tThe US Army is evaluating new, insensitive explosives to produce safer munitions. Two potential new components are 2,4-dinitro anisole (DNAN) and N-methyl paranitro aniline (MNA), which would eventually make their way to waste streams generated in the production and handling of new munitions. The effectiveness of anaerobic fluidized-bed bioreactors (AFBB) was studied for treatment and transformation of these two new chemical components in munitions. Each compound was fed into a separate reactor and monitored for removal and transformation, using ethanol as the electron donor. The results show that both were degradable using the AFBB system. DNAN was found to transform into diaminoanisole and MNA was found to transform into N-methyl-p-phenylenediamine. Both of these by-products appeared to form azobond polymers after exposure to air. To test the resilience of the reactors, the compounds were removed from the feed streams for 3 week and then reintroduced. DNAN showed that a re-acclimation period was necessary for it to be degraded again, while MNA was removed immediately upon reintroduction. The AFBB technology was shown here to be an effective means of removing the new munitions, but produce secondary compounds that could potentially be just as harmful and require further study.

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