• 공업화학
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• 제17권5호
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• pp.552-556
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• 2006

본 연구에서는 70000 mg/L 가량의 고농도 철(III)-에틸렌디아민테트라아세트산(Fe(III)-EDTA)을 함유하고 있는 원전 증기발생기 화학 세정 폐액의 처리를 위해 펜톤 반응을 사용하였다. Fe(III)-EDTA 분해실험은 모사 폐액 뿐 아니라 실제 폐액을 가지고도 수행되었다. 폐액에 주입된 과산화수소의 양과 폐액의 pH가 Fe(III)-EDTA 분해에 미치는 영향이 정량적으로 평가되었고, 다양한 측면에서 고찰되었다. 분해효율이 최대가 되는 최적의 pH는 폐액에 주입된 과산화수소의 양에 의존하였다. 즉, 폐액에 주입된 과산화수소의 양이 다를 때 최대 분해효율이 얻어지는 pH가 달랐다. Fe(III)-EDTA의 분해를 위한 적정 조건은 폐액의 초기 pH가 9이고 과산화수소 주입량이 24.7 mol ($H_{2}O_{2}$)/mol (Fe(III)-EDTA)일 때였다.

• 한국응용과학기술학회지
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• 제29권1호
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• pp.108-115
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• 2012

수침목재유물은 해저, 호저, 저습지등에서 발견되며 물속에서 외부로 아무런 조치 없이 나오게 되면 수축과 변형을 일으키게 된다. 따라서 보존처리는 목재내부의 물을 화학약품과 치환하고 강도와 치수의 안정화를 이루는 것이다. 이중 EDTA와 PEG는 수침목재유물 보존처리에 가장 많이 사용되는 약품중 하나이다. EDTA는 발굴출토된 목재의 흑화현상의 원인인 타닌산제2철에서 Fe-EDTA의 형태로 흑화현상을 제거한다. 보존처리 후 발생하는 폐 EDTA 용액으로부터 HCl을 첨가하여 Fe-EDTA에서 $Fe^{3+}$를 분리해 내고 강산성에서 EDTA가 석출되는 원리를 이용하여 EDTA의 침전물을 획득하여 재활용하였다. PEG는 수침목재유물의 강화처리에 사용되며 목재 내에서 추출되는 착색유기물에 의해 용액의 색이 검은색으로 변화하게 되며, 폐 PEG 용액을 $H_2O_2$를 이용한 산화작용으로 용액 내에 존재하는 착색유기물을 분해하고 색을 되돌려 재활용하였다.

• Environmental Engineering Research
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• 제13권3호
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• pp.131-135
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• 2008

In this study, Fe(VI) was employed as a multi-functional agent to treat the simulated industrial wastewater contaminated with Cu(II)-EDTA through oxidation of EDTA, decomplexation of Cu(II)-EDTA and subsequent removal of free copper through precipitation. The decomplexation of $10^{-4}\;M$ Cu(II)-EDTA species was performed as a function of pH at excess concentration of Fe(VI). It was noted that the acidic conditions favor the decomplexation of Cu(II)-EDTA as the decomplxation was almost 100% up to pH 6.5, while it was only 35% at pH 9.9. The enhanced degradation of Cu(II)-EDTA with decreasing the pH could be explained by the different speciation of Fe(VI). $HFeO_4^-$ and $H_2FeO_4$, which are relatively more reactive than the unprotonated species $FeO_4^{2-}$, are predominant species below neutral pH. It was noted that the decomplexation reaction is extremely fast and within 5 to10 min of contact, 100% of Cu(II)-EDTA was decomplexed at pH 4.0. However, at higher pH (i.e., pH 10.0) the decomplexation process was relatively slow and it was observed that even after 180 min of contact, maximum ca 37% of Cu(II)-EDTA was decomplexed. In order to discuss the kinetics of the decomplexation of Cu(II)-EDTA, the data was slightly fitted better for the second order rate reaction than the first order rate reaction in the excess of Fe(VI) concentration. On the other hand, the removal efficiency of free Cu(II) ions was also obtained at pH 4.0 and 10.0. It was probably removed through adsorption/coagulation with the reduced iron i.e., Fe(III). The removal of total Cu(II) was rapid at pH 4.0 whereas, it was slow at pH 10.0. Although the decomplexation was 100% at lower pH, the removal of free Cu(II) was relatively slow. This result may be explicable due to the reason that at lower pH values the adsorption/coagulation capacity of Fe(III) is greatly retarded. On the other hand, at higher pH values the decomplexation of Cu(II)-EDTA was partial, hence, slower Cu(II) removal was occurred.

• 대한화학회지
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• 제12권3호
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• pp.114-120
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• 1968

Fe-EDTA complex, which is easily formed when Fe salt and EDTA.2Na are mixed in the aqueous medium, is found to be a very effective catalyst in the dehydropolycondensation of aminophenols. In the dehydropolycondensation of aminophenols, the catalyst, Fe(Ⅲ)-EDTA complex (higher oxidation state) is reduced to less stable Fe(Ⅱ)-EDTA complex (lower oxidation state), and the latter is easily oxidized by air to the original higher oxidation state complex, therefore the catalytic action of Fe-EDTA complex is found to be recycled effectively. Under the catalytic action of the above mentioned complex, p-aminophenol is polymerized in the aqueous medium to form the oligomers of p-aminophenol, which the degree of polymerization to be 5 or more. The oligomers formed contain partly quinone nucleus as well as amino and hydroxyl groups. In this study, the effects of the solvents and characteristics of the oligomers are discussed. These types of polymerizations catalyzed by the metallic chelate compounds are considered to be very closely related to the reactions in the living matters.

• Journal of Plant Biotechnology
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• 제50권
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• pp.183-189
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• 2023

This study investigated the impact of two distinct MS basal media: one containing FeNaEDTA and the other FeEDDHA, on the growth of five unique gerbera cultivars (Shy Pink, Pink Holic, Breeze, Harmony, Snow Dream). Notably, the response to these media types varied significantly among the cultivars, particularly concerning leaf yellowing and plant growth. 'Shiny Pink' and 'Pink Holic' exhibited leaf yellowing on the FeNaEDTA-containing medium but displayed leaf greening on the FeEDDHA-containing medium. In contrast, 'Snow Dream,' 'Harmony,' and 'Breeze' remained unaffected on both medium types. However, the FeNaEDTA-containing medium promoted higher plant height and petiole length in 'Breeze,' 'Harmony,' and 'Snow Dream' than the FeNaEDTA-containing medium did. A promotive effect of silver nanoparticles (AgNPs) on plant growth and leaf greening was observed in 'Pink Holic,' particularly on the FeNaEDTA-containing medium, while the addition of AgNPs to the FeEDDHA-containing medium negatively affected plant growth. These results highlight the substantial influence of medium type, specifically the presence of FeNaEDTA or FeEDDHA, on gerbera growth responses, emphasizing the critical role of medium selection in gerbera propagation. Additionally, when contemplating the addition of AgNPs for in vitro gerbera propagation, it is crucial to consider the medium type.

• 분석과학
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• 제24권3호
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• pp.231-235
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• 2011

A spectrofluorimetric method for the determination of EDTA in real samples such as mayonnaise, powder detergent and cleansing cream with tiron (4,5-dihydroxy-1,3-benzenedisulfonic acid) as a fluorimetric reporter was developed. When tiron is chelated with Cu(II), the fluorescent intensity is decreased by a quenching effect. However, when Cu(II)-tiron chelate reacts with EDTA, fluorescent intensity is increased as tiron is released. Several experimental conditions such as pH of the sample solution, the amount of Cu(II), the amount of tiron, heating temperature and heating time were optimized. Fe(III) interfered more seriously than any other ions, interference of Fe(III) could be disregarded, because Fe(III) was scarcely contained in selected real samples. The linear range of EDTA was from $8.0{\times}106{-8}\;M$ to $2.0{\times}10^{-6}\;M$. With this proposed method, the detection limit of Fe(III) was $5.2{\times}10^{-8}\;M$. Recovery yields of 92.7~99.3% were obtained. Based on experimental results, it is proposed that this technique can be applied to the practical determination of EDTA.

• 한국자원식물학회지
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• 제32권6호
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• pp.677-682
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• 2019

Hand leaf thinning for improvement of fruit coloration and quality is one of the most labor-consuming works in Korean apple cultivation. The study was aimed at investigating whether foliar application of two chelate compounds (Cu-EDTA, Fe-EDTA) could defoliate effectively 'Hongro'/M.9 apple leaves and enhance fruit coloration and quality. At 30 days before harvest, foliar spray with two chelate compounds defoliated significantly the apple leaves. Chelate treatments did not affect the leaf chlorophyll content. High concentration of chelates decreased drastically photosynthetic rate of true leaves, and then it stayed in low levels, whereas low levels of chelates reduced sharply the photosynthetic rate but it was gradually restored over time. Cu-EDTA regardless of its concentration triggered higher defoliation compared to Fe-EDTA. Consequently, higher defoliation improved light interception of fruits and accumulated more anthocyanin. Particularly, Cu-EDTA could target mainly fruit cluster leaves which affect directly light interception of the fruits, i.e. more selective defoliants compared to Fe-EDTA. However, 3% Cu-EDTA rather defoliated excessively, accompanying with reduction of fruit weight and soluble solids. Therefore, our results suggest that 1% Cu-EDTA which defoliates properly the fruit cluster leaves could improve coloration and quality of 'Hongro'/M.9 apple fruits.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2004년도 추계학술발표회 발표논문집
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• pp.787-788
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• 2004

• 한국지반환경공학회 논문집
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• 제13권10호
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• pp.69-76
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• 2012

본 연구에서는 전자빔공정(Electron beam process, E-beam)에서 생성되는 수산화라디칼의 생성특성을 조사하였고, 이 공정에 첨가제로 과산화수소와 $Fe^{3+}-EDTA$을 이용한 펜타클로로페놀(Pentachlorophenol, PCP)의 분해 특성을 조사하였다. 이를 위해 수산화라디칼의 측정은 벤조산(Benzoic Acid, BA)에 의한 hydroxylation으로 생성된 hydroxybenzoic acid(OHBA)의 농도를 정량화하여 수행하였다. 실험결과, 실제 측정된 수산화라디칼의 농도는 예측된 수산화라디칼에 비해 낮은 농도로 나타났으며, 이것은 아마도 E-beam 에너지의 조사와 동시에 형성되는 다양한 반응성 화학종이 수산화라디칼을 스케빈져(scavening)할 것으로 생각되었다. 특히, 1mM 이하의 과산화수소 주입은 PCP 분해를 촉진시킬 수 있으나 그 이상의 과산화수소의 주입은 오히려 PCP의 분해를 감소시키거나 PCP의 부산물인 염소이온과 Carbon yield(%)를 증가시키는 요인으로 작용하였다. 반면에, $20{\mu}M$의 $Fe^{3+}-EDTA$ 첨가는 효과적으로 PCP를 제거하였고, 이에 따른 G-value도 증가한 것으로 나타났다. OHBA의 형성과 PCP의 분해를 고려하여 보면, 결과적으로 E-beam공정에 가하는 $Fe^{3+}-EDTA$의 첨가는 상대적으로 낮은 세기에서도 효과적으로 PCP를 처리할 수 있을 것으로 생각된다.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2003년도 가을 학술논문집
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• pp.78-82
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• 2003

국내 원전에서 증기발생기 세정 후 발생되는 Fe-EDTA 함유 폐액 처리를 위한 초임계수 산화공정 (Supercritical Water Oxidation Process), 광촉매 산화 공정 (Photocatalyst Oxidation Process) 및 DBD 상온 플라즈마 공정 (Dielectric Barrier Discharge Atmospheric Pressure Plasma Process)이 평가되었다. 초임계수 산화 공정에 의해 99.98 %이상의 EDTA 전환율을 나타내어 EDTA 처리를 위한 효과적인 반응공정임을 확인하였으나 공정의 안정성, 부식 방지대책 등이 마련되어야 할 것으로 판단된다. 광촉매산화공정으로는 10 % 정도의 낮은 EDTA전환율을 보여 세정폐액 처리 공정으로는 부적합한 것으로 나타났다. DBD를 이용한 Methylene Blue 분해 결과 저 에너지 소비율로 높은 유기물 분해 효율을 얻을 수 있었으나 실 EDTA 공정에의 적용 및 공정 규모 확장 등에 대한 향후 연구 평가가 필요한 것으로 사료된다.