• 한국토양환경학회지
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• 제4권3호
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• pp.85-93
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• 1999

유기 염소계 화합물과 니트로기 방향족 화합물 같은 난분해성 유해물질을 처리함에 있어, 0가 철 분말의 사용은 최근에 가장 활발히 논의되고 있는 기술 가운데 하나이다. 본 연구에서는 나노크기의 0가 철 분말을 실험실에서 만들어 유기 염소계 화합물의 탈염소화 반응과 니트로기 방향족 화합물의 니트로기 변환실험을 혐기성 회분식 반응조에서 실시하였다. 매우 큰 비표면적과 높은 반응성을 가지고 있는 나노크기 0가 철 입자는 10mg/$\ell$로 농도수용액상에 존재하는 TCE, 클로로포름, 니트로 벤젠, 니트로 톨루엔, 디니트로 밴젠, 디니트로 톨루엔등의 물질을 상온.상압의 조건에서 빨리 제거할 수 있었다. 본 연구에서는 반응 시간 30분 안에 TCE는 에탄으로, 클로로포름은 메탄으로 탈염소화 되었고, 니트로기 방향족 화합물의 니트로기는 모두 아민기로 변환되었다. 이러한 결과들은 유기 염소계 화합물과 니트로기 방향족 화합물 같은 난분해성 유해물질로 오염된 지하수나토양을 복원함에 있어, 나노크기의 0가 철 분말을 이용한 화학적 처리기술의 잠재성을 나타내주는 것이다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권6호
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• pp.73-84
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• 2015

Nine plant species were selected through vegetation survey at three military shooting ranges at northern Gyeonggi Province. Plants were germinated in normal soil and three seedlings were transplanted to a bottom sealed pot containing sandy loam soils contaminated with either RDX (291 mg/kg) or TNT (207 mg/kg). Planted, blank (without plant), and control (without explosive compound) pots were grown in triplicate at a green house for 134 days. During cultivation, transplanted plants exhibited chlorosis and necrosis in flower and leaf by explosive toxicity and stress. Only three plants, Wild soybean, Amur silver grass, Reed canary grass, survived in TNT treated pot, while seven plant species except for field penny cress and jimson weed, thrived in RDX treated pot. Appreciable amount of TNT (61.6~241.2 mg/g-D.W.) was detected only in plant roots. Up to 763.3 mg/g-D.W. along with 4-amino-2,6-dinitrotoluene, an intermediate of TNT, accumulated in the root of wild soybean. In addition, azoxy compounds, abiotic intermediates of TNT, were detected in TNT treated soils. RDX absorbed average 1,839.95 mg/kg in shoot and 204.83 mg/kg in root. Most of TNT in plant was accumulated in underground part whereas RDX was localized in aerial part. Material balance calculation showed that more than 95% of the initial TNT was removed in the planted pots whereas only 60% was removed in the blank pot. The amount of RDX removed from soil was in the order of Amur Silver Grass (51%) > Chickweed (43%) > Evening primrose (38%). Based on the results of pot cultures, Amur silver grass and Reed canary grass are selected as tolerant remedial plants for explosive toxicity.

• 한국물환경학회지
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• 제31권5호
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• pp.468-475
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• 2015

Various methods to degrade explosives efficiently in natural soil and water that include trinitrotoluene (TNT) have been studied. In this study, TNT in water was degraded by reduction with palladium (Pd) catalyst impregnated onto alumina (henceforth Pd-Al catalyst) and formic acid. The degradation of TNT was faster when the temperature of water was high, and the initial TNT concentration, pH, and ion concentration in water were low. The amounts of Pd-Al catalyst and formic acid were also important for TNT degradation in water. According to the experimental results, the degradation constant of TNT with unit mass of Pd-Al catalyst was $8.37min^{-1}g^{-1}$. The degradation constant of TNT was higher than the results of previous studies which used zero valent iron. 2,6-diamino-4-nitrotoluene and 2-amino-4,6-dinitrotoluene were detected as by-products of TNT degradation showing that TNT was reduced. The by-products of TNT were also completely degraded after reaction when both Pd-Al catalyst and formic acid existed. Even though there are several challenges of Pd-Al catalyst (e.g., deactivation, poisoning, leaching, etc.), the results of this study show that TNT degradation by Pd-Al catalyst and formic acid is a promising technique to remediate explosive contaminated water and soil.

• Advances in environmental research
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• 제1권1호
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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.