• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.2
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• pp.282-288
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• 2014

In this research, we investigated synthetic method of 2,6-DANT that can be used as a chain extender of urethane/urea and epoxy materials in a demilitarization method via chemical transformations considering environmental, economical aspects and stability of process. We was able to identify through GC monitoring that 2,4-DANT and 2,6-DANT were produced when we inject 'hydrazine monohydrate 3.3 eq. by TNT 1 eq.' with a fine metering pump for 30 minutes and then, reflux for an additional 2 hours. We was able to isolate only 2,6-DANT(99.3% purity and 45.0% yield) from mixture of 2,4-DANT and 2,6-DANT through the separating and refining methods using 2,6-DANT solubility in methanol and crystallinity of 2,6-DANT.

• Korean Journal of Microbiology
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• v.38 no.4
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• pp.247-253
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• 2002

The cellular responses of TNT-degrading bacterium, Stenotrophomonas sp. OK-5 to explosive 2,4,6-trini-trotoluene (TNT) as an environmental contaminant were examined. Survival of the strain OK-5 with time in the presence of different concentrations of TNT under sublethal conditions was monitored, and viable counts paralleled the production of the stress shock proteins in this bacterium. Total cellular fatty acids analysis showed that strain OK-5 produced or disappeared several different kinds of lipids when grown on TNT media than when grown on TSA. Under scanning electron microscope, the cells treated with 0.5 mM TNT for 12 hrs showed irregular rod shapes with wrinkled surfaces. Analyses of SDS-PAGE and Western blot using anti-DnaK and anti-GroEL revealed that several stress shock proteins including 70 kDa DnaK and 60 kDa GroEL in strain OK-5 were newly synthesized at different TNT concentrations in exponentially growing cultures. 2-D PAGE of soluble protein fractions from the culture of OK-5 exposed to TNT demonstrated that approximately 300 spots were observed on the silver stained gel ranging from pH 3 to pH 10. Among them, 10 spots significantly induced and expressed in response to TNT were selected and analyzed. As the result of internal amino acid sequencing with ESI-Q TOF, two proteins, spot #1 and spot #10 were assigned the DnaK protein XF2340 of Xylella fastidiosa and stress-induced protein of Mesorhizobium loti, respectively.

• Journal of Soil and Groundwater Environment
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• v.11 no.6
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• pp.76-82
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• 2006

Fenton's reaction are difficult to apply in the field due to the low pH requirements for the reaction and the loss of reactivity caused by the precipitation of iron (II) at neutral pH. Moreover, Fenton-like reactions using iron mineral instead of injection of iron ion as a catalyst are operated to get high removal result at low pH. Because hydroxyl radical can generate at the surface of iron mineral, there are competition with a lot of hydroxide at around neutral pH. On the other side, to operate Fenton's reaction series at neutral pH, modified Fenton reaction is suggested. The complexes, composed by iron ions (ferrous ion or ferric ion)-chelating agent, could be acted as a catalyst and presented in the solution at neutral pH. However, modified Fenton reaction requires a lot of hydrogen peroxide. Accordingly, the purpose of this experiment was to effectively combine Fenton-like reaction and modified Fenton reaction for extending application of Fenton's reaction. i.e., injecting chelating agents in Fenton-like reaction at around neutral pH is increasing the concentration of dissolved iron ion and highly promoting the oxidation effect. 2,4,6-trinitrotoluene (TNT) was used as a probe compound for comparing reaction efficiencies in this study. If the concentration of dissolved iron ion in combined Fenton process were existed more than 0.1 mM, the total TNT removal were increased. Magnetite-NTA system showed the best TNT removal (76%) and Magnetite-EDTA system indicated about 56% of TNT removal. The results of these experiments proved more promoted 40-60% of TNT removal than Fenton-like reaction's.

• Korean Journal of Microbiology
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• v.38 no.2
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• pp.67-73
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• 2002

The cellular responses of soil-borne bacterium, Pseudomonas sp. HK-6 to explosive 2,4,6-trinitrotoluene (TNT) were examined. Two stress shock proteins (SSPs), approximately 70-kDa DnaK and a 60-kDa GroEL were found in HK-6 cells in response to TNT. Analyses of SDS-PAGE and Western blot using anti-DnaK and GroEL revealed that SSPs were induced in HK-6 cells exposed to 0.5 M of TNT far 6-12 hrs. The maximum induction of proteins was achieved at 8-hr incubation point after HK-6 cells'exposure to TNT. Similar SSPs were found to be induced in HK-6 cells by heat shock (shift of temperature, from $30^{\circ}C$ to $42^{\circ}C$) or cold shock (shift of temperature,$30^{\circ}C$ to $4^{\circ}C$).2D-PAGE of soluble protein tractions from the culture of Pseudomonas sp. HX-6 exposed to TNT demonstrated that approximately 450 spots were observed on the silver stained gels ranging from pH 3 to pH 10. Among them, 12 spots significantly induced and expressed in response to TNT were selected and analyzed. Approximately 60-kDa protein, which was assumed highly expressed on the gel, was used for amino acid sequencing. N-terminal microsequencing with in-gel digestion showed that N-terminal sequence of the TNT-induced protein, <$^1XXAKDVKFGDSARKKML^17$, shared extensive similarity with $^1XXAKDVKFGDSARKKML^17$, N-terminal sequence of (P48216) GroEL of Pseudomonas putida.

• Korean Chemical Engineering Research
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• v.45 no.3
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• pp.298-303
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• 2007

Several combinations of ozone based advanced oxidation processes were tested for the treatment of red water (RW) containing recalcitrant chemical pollutants produced from 2,4,6-trinitrotoluene (TNT) manufacturing process. $O_3$, $UV/O_3$, $UV/O_3/H_2O_2$, $UV/O_3/H_2O_2/Fe^{2+}$ processes were tested for the treatment of RW. The order of organic and color removal efficiency was found to be : $O_3{\leq}UV/O_3$ < $UV/O_3/H_2O_2$ < $UV/O_3/H_2O_2/Fe^{2+}$. The optimum conditions for the removal of organic and color in the $UV/O_3/H_2O_2/Fe^{2+}$ process were 0.053 g/min of ozone flow rate, 10 mM of $H_2O_2$ concentration and 0.1 mM of $FeSO_4$ concentration. Organic and color removal efficiencies were 96 and 100 % respectively in the $UV/O_3/H_2O_2/Fe^{2+}$ process. tert-butyl alcohol (t-buOH) was used as the hydroxyl radical scavenger. Enhancement of hydroxyl radical production was achieved by the combination of ozone with several oxidants such as UV, $H_2O_2$, $Fe^{2+}$.

• Mycobiology
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• v.37 no.1
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• pp.17-20
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• 2009

White-rot fungus Irpex lacteus degraded TNT significantly in proportion to the culture time. After 48 h incubation, about 95% of TNT was degraded. Two reduced metabolites were identified as 4-amino-2,6-dinitrotoluene (4-ADNT) and 2-amino-4,6-dinitrotoluene (2-ADNT) which was further degraded.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.2
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• pp.303-311
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• 2000

This study was conducted to find an optimal TNT transformation condition with the addition of different carbon and energy sources in a batch reactor. When TNT and nitrate were present in the medium, the cell growth and TNT transformation was slower because nitrate and TNT was competitively served as electron acceptor. Transformation of TNT was faster when TNT in the medium was nitrogen source and acetate as a carbon source. Cell growth and nitrate transformation was slower when yeast extract was not present in the medium. The proposed intermediates of TNT biotransformation from the earlier studies was not detected in this experiment but the intermediates are tentatively proposed as nitro and amino-free compounds. These results should be helpful for the operation of the munition waste treatment in the future.

• Advances in environmental research
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• v.1 no.1
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• pp.1-14
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• 2012

We demonstrated that reductive degradation of 2,4,6-Trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (Royal Demolition Explosive, RDX) can be enhanced by bio-reduced iron-bearing soil minerals (IBSMs) using Shewanella putrefaciens CN32 (CN32). The degradation kinetic rate constant of TNT by bio-reduced magnetite was the highest (0.0039 $h^{-1}$), followed by green rust (0.0022 $h^{-1}$), goethite (0.0017 $h^{-1}$), lepidocrocite (0.0016 $h^{-1}$), and hematite (0.0006 $h^{-1}$). The highest rate constant was obtained by bio-reduced lepidocrocite (0.1811 $h^{-1}$) during RDX degradation, followed by magnetite (0.1700 $h^{-1}$), green rust (0.0757 $h^{-1}$), hematite (0.0495 $h^{-1}$), and goethite (0.0394 $h^{-1}$). Significant increase of Fe(II) was observed during the reductive degradation of TNT and RDX by bio-reduced IBSMs. X-ray diffraction and electron microscope analyses were conducted for identification of degradation mechanism of TNT and RDX in this study. 4-amino-dinitrotoluene were detected as products during TNT degradation, while Hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine, Hexahydro-1,3-dinitroso-5-nitro-1,3,5triazine, and Hexahydro-1,3,5-trinitroso-1,3,5-triazine were observed during RDX degradation.

• Journal of the Korean Geosynthetics Society
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• v.21 no.3
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• pp.21-27
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• 2022

For carbon neutrality, interest in R&D and infrastructure construction for hydrogen energy, an eco-friendly energy source, is growing worldwide. In particular, for hydrogen stations installed in downtown areas, underground hydrogen infrastructure are being considered to increase a safety distance from hydrogen tank explosions to adjacent structures. In order to design an appropriate location and depth of the underground hydrogen infrastructure, it is necessary to evaluate the impact of the explosion of the underground hydrogen infrastructure on adjacent structures. In this paper, a numerical model was developed to analyze the effect of the underground hydrogen infrastructure explosion on adjacent structures, and the over pressure of the hydrogen tank was evaluated using the equivalent TNT (Trinitrotoluene) model. In addition, parametric analysis was performed to estimate the stability of adjacent structures according to the construction conditions of the underground hydrogen infrastructure.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.1
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• pp.1-10
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• 2005

The purpose of this study was to evaluate the potential of a gamma irradiation to decompose 2,4,6-trinitrotoluene(TNT) in an aqueous solution. The decomposition reaction of TNT by gamma irradiation was a pseudo first-order kinetic over the applied initial concentrations($25{\sim}100mg/L$). The dose constant was strongly dependent on the initial TNT concentration. The removal of TNT was more efficient at pH below 3 and at pH above 11 than at neutral pH(pH 5-9). The required irradiation dose to remove over 99% of TNT was 40, 80 and 10 kGy, individually at pH 2, 7 and 13. The dose constant was increased by 1.6 fold and over 15.6 fold at pH 2 and 13, respectively, when compared with that at pH 7 When irradiation dose of 200 kGy was applied, the removal efficiencies of TOC were 91, 46 and 53% at pH 2, 7 and 13, respectively. Ammonia and nitrate were detected as the main nitrogen byproducts of TNT and glyoxalic acid and oxalic acid were detected as organic byproducts. The results showed that a gamma irradiation was an attractive method for the decomposition of TNT in an aqueous solution. However, regarding the application of high energy radiation for the TNT decomposition and mineralization, an application of an acidic pH below 3 to the solution before irradiation should be considered.