• Journal of Korean Society on Water Environment
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• v.20 no.1
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• pp.32-36
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• 2004

In this study, uptake and translocation of 2,4,6-trinitrotoluene(TNT) by plant in a hydroponic culture was quantified with two indigenous plant species, Aeschynomene indica and Abutilon avicennae on various initial concentrations of TNT ranging from 20 to 80 mgTNT/L. Experiments were sterilized to exclude the activity of microorganisms and conducted in duplicate. Weight loss of two plant species in added TNT culture media was higher than in control. At over 2OmgTNTIL, there appeared to be phytotoxicity from TNT as indicated by severe yellow-chlorosis and increase of falling leaves. TNT removal rate normalized(K) to the plant fresh weight of Abutilon avicennae and Aeschynomene indica was that the higher TNT concentrations resulted in lower TNT removal rate normalized(K) to the plant fresh weight. Approximately 96% of the TNT in viable microflora-hydroponic culture was removed after 96h of the experiments.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.5
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• pp.476-485
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• 2005

In this study, abiotic transformation of TNT reduction products via oxidative-coupling reaction was investigated using Mn oxide. In batch experiments, all the reduction products tested were completely transformed by birnessite, one of natural Mn oxides present in soil. Oxidative-coupling was the major transformation pathway, as confirmed by mass spectrometric analysis. Using observed pseudo-first-order rate constants with respect to birnessite loadings, surface area-normalized specific rate constants, $k_{surf}$, were determined. As expected, $k_{surf}$ of diaminonitrotoluenes (DATs) ($1.49{\sim}1.91\;L/m^2{\cdot}day$) are greater about 2 orders than that of dinitroaminotoluenes (DNTs) ($1.15{\times}10^{-2}{\sim}2.09{\times}10^{-2}\;L/m^2{\cdot}day$) due to the increased number of amine group. In addition, by comparing the value of $k_{surf}$ between DNTs or DATs, amino group on ortho position is likely to be more preferred for the oxidation by birnessite. Although cross-coupling of TNT in the presence of various mediator compounds was found not to be feasible, transformation of TNT by reduction using $Fe^0$ followed by oxidative coupling using Mn oxide was efficient, as evaluated by UV-visible spectrometry.