• 한국환경과학회지
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• 제17권5호
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• pp.547-553
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• 2008

For the RhB removal from the wastewater, electrochemical method was adapted to this study. Three dimensionally stable anode (Pt, Ir and Ru) and graphite and Ru cathode were used. In order to identify decolorization, the effects of electrode, current density, electrolyte and air flow rate were investigated. The effects of electrode material, current, electrolyte concentration and air flow rate were investigated on the decolorization of RhB. Electro-Fenton's reaction was evaluated by added $Fe^{2+}$ and $H_2O_2$ generated by the graphite cathode. Performance for RhB decolorization of the four electrode systems lay in: Ru-graphite > Ru-Ru > Ir-graphite > Pt-graphite. A complete color removal was obtained for RhB (30 mg/L) at the end of 30 min of electrolysis under optimum operations of 2 g/L NaCl concentration and 2 A current. $Fe^{2+}$ addition increased initial reaction and decreased final RhB concentration. However the effect was not high.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XII)
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• pp.403-408
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• 2003

A newly isolated Rhodopseudomonas palustris P4 could decolorize various synthetic dyes containing different chromogenic groups such as azo linkage (Crocein Orange G, New Coccine, Chromotrope FB, Congo Red, Remazol Black B), anthraquinone Reactive blue 2, or indigo Indigo Carmine. Among them, the degradation rate of Black B was studied in detial. Degradation of Black B followed the Arrhenius equation in 25 - $40^{\circ}C$ with an activation energy of 7.79 kcal/mol. Optimum pH was 8. Glucose in the range of 5 - 50g/l did not affect the Black B decolorization. When Black B increased from 25 mg/l to 2000 mg/l, decolorization activity increased almost linearly but the extent of decolorization was constant at about 86% irrespective of dye concentration. Analyses by HPLC revealed that the Black B molecules were partially degraded and some chromogenic intermediates were produced. These results indicate that Rps. palustris P4 has an outstanding capability to degrade various dyes.

• Fibers and Polymers
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• 제7권2호
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• pp.112-116
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• 2006

Caprolactam is the most important raw material for making Nylon 6 fibers and its quality directly determines the quality of Nylon. So it is necessary to study the techniques and methods to remove the colorful impurities from caprolactam. In this paper, the decolorization of caprolactam aqueous solution by anion exchange resins was studied and the decoloring abilities of five commercial resins were investigated. The regeneration of the resins was also studied, too. This study shows that the resin AMTX202 have excellent decoloring ability in the column experiment and that the decoloring efficiency is correlated with the volume of resins packed and is slightly affected by the flow rate and regenerating times. The fact that the resins can be regenerated and reused without affecting the efficiency of decolorization will decrease the cost of the treatment and operation in the industry. The adsorption of colored compounds with anion exchange resins in the packed columns seems to be technically feasible.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 1998년도 총회 및 춘계 학술발표회 논문집
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• pp.91-95
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• 1998

본 연구의 목적은 산업활동에 많이 이용되고 환경학적으로 난분해성으로 알려졌으며, 특히 일반적인 미생물에 위한 생분해가 용이하지 않은 대표적인 방향족 화합물인 아조염료의 생분해능이 우수한 방선균을 토양에서 분리하여 그 분해특성을 연구하는데 있다. 본 연구실에서는 용인지역에서 무작위로 채취한 토양에서 방선균들을 분리하고, 이들중 아조계 화합물의 생분해능이 우수한 토양방선균 AD001을 대표적인 아조계화합물인 censored를 model compound로 이용하여 분리해 내었다. 방선균 AD001은 congored가 포함된 agar배지에서 censored를 아주 우수하게 decolorization 시킴이 관찰되었다. 이미 아조염료를 우수하게 분해한다고 알려져 있는 Streptomyces viridosporus T7A와 비교 실험을 수행한 결과, S. viridosporus는 cellulose를 탄소원으로 사용할 때 확실한 congored의 decolorization을 보인 반면 AD001의 경우 sucrose를 탄소원으로 사용할 때 더욱 뚜렷한 congored의 decolorization 현상이 관찰되었다. 또한 이런 분해특성의 특이성을 관찰하기 위해 구조적으고 상이한 new fuchsin으로 실험한 결과, 염료의 농도를 0.005% 주었을 때 S. viridosporus는 성장을 하지 못한 반면 AD001의 경우 배지에 포함된 new fuchsin을 확실하게 decolorization 시킴도 관찰할 수 있었다. 이러한 실험결과는 토양 방선균 AD001이 환경학적으로 아주 유용하게 이용될 수 있음을 제시하고 있다.

• Journal of the Korean Wood Science and Technology
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• 제32권3호
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• pp.79-87
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• 2004

The objectives of this study were to select superior fungus for lignin degradation and to decolor dyes by selected fungus. Ligninolytic fungi were screened and isolated from decayed woods. Ten ligninolytic fungi were selected by ligninolytic enzyme activity on the PDA media containing rhemazol brilliant blue R, guaiacol and gallic acid. Their lignin degradation abilities were tested on the extractive-free wood powder of Quercus acutissima and Pinus densiflora. As a result, 8J-28 was selected as superior fungus for lignin degradation. Also, decolorization abilities of dyes were examined by shaking and static culture. And congo red, crystal violet, poly R-478, methylene blue used to investigate decolorization abilities of dyes. As a result, 8J-28 showed over 90% in decolorization of congo red, crystal violet, poly R-478.

• KSBB Journal
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• 제15권1호
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• pp.66-71
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• 2000

Geotrichum candidum (KCTC 6195)를 이용하여 색도제거를 위한 최적조건은 초기 pH 6, $30^{\circ}C$, glucose 농도 30 g/L이었으며 빛은 세포성장과 색도제거에 영향을 주지 않았다. 한편, 세포성장과 색도제거를 위해서는 세포의 성장원(glucose)이 필수적이었다. 염료의 종류에 따라 색도제거량과 속도는 차이가 있지만 분산염료, 산성염료, 반응염료에 대해 색도제거가 고체배치와 액체배치에서 가능했으며 Acid goange 10 염료의 경우 배양 후 120 시간 후에는 초기 100 ppm에서 91%로, 초기 500ppm에서 84%까지 색도제거되는 것을 알 수 있었다. 색도제거에서 Acid red 1: 19.8%, Acid red 88, 73%, Acid orange 10; 12.1%, Reactive blue 19; 14.6%가 흡착으로 제거되었다. 이로서 효소에 의한 색도제거뿐만 아니라 흡착에 의해 색도제거됨을 알 수 있었다. 2일간 배양하고 glucose를 첨가하여 1일간 추가 배양한 경우 97%까지 색도제거 되었다.

• 한국염색가공학회지
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• 제11권2호
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• pp.19-26
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• 1999

Strains degrading and decolorizing acid dyes, Nylosan red E-BL 150%. were isolated from natural system, was named as ARK3. The optimal culture conditions of temperature and pH were $35^\circ{C}$, 7.0, respectively. Growth rate of cells in conditions of aerobic shaking more than standing culture conspicuously increased, and optical density of those to strain ARK3 were found as 1.38 and 0.25 after 42 hrs. Decolorization efficiency in batch culture which used as immobilization media to natural zeolite was 15% after 6 hrs, while suspension culture was 5%, also its of immobilization and suspension culture were 90% and 85% after 48 hrs, respectively. Decolorization efficiency of air-lift bioreactor was more than 90% to a dilution rate of $0.038hr^{-1}$, but that was decreased as 70%, when the dilution rate was $0.05hr^{-1}$. Even though at maximum dilution rate of this study, there was not appeared "wash out" phenomienon of biomass. Decolorization efficiency was 97.7% at a dilution rate of $0.025hr^{-1}$, when influent dye concentration was $100mg/\ell$. But if influent dye concentration increased as $150mg/\ell$, even though MLVSS increased, that of treatment water decreased as 93%. Also, when influent dye concentration increased as $200mg/\ell$ and $300mg/\ell$, decolorization efficiencies of treatment water abruptly decreased as 85% and 63%, respectively. Decolorization efficiency was more than 92% to the limit volumetric loading rate of $3.75mg/\ell\cdot{hr}$hr, without regard to variation of influent dye concentration or hydraulic retention time. if volumetric loading rate was more than $3.80mg/\ell\cdot{hr}$, at same condition, decolorization efficiency was lower decrease of retention time than increase of influent dye concentration.entration.

• 한국환경과학회지
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• 제25권12호
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• pp.1717-1726
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• 2016

In this study, the reductive decolorization of three acid and basic dyes using modified zero-valent iron (i.e., acid-washed iron (Aw/Fe) and palladium coated iron (Pd/Fe)) at various pH conditions (pH 3~5) was experimentally investigated and the decolorization characteristics were evaluated by analyzing the absorbance spectra and reaction kinetics. In the case of acid dyes such as methyl orange and eriochrome black T, color removal efficiencies increased as initial pH of the dye solution decreased. However, the color removal of methylene blue, a basic dye, was not affected much by the initial pH and more than 70% of color was removed within 10 min. During the decolorization reaction, the absorbance of methyl orange (${\lambda}_{max}=464nm$) and eriochrome black T (${\lambda}_{max}=528nm$) decreased in the visible range but increased in the UV range. The absorbance of methylene blue (${\lambda}_{max}=664nm$) also decreased gradually in the visible range. Pseudo-zero order, pseudo-first order, and pseudo-second order kinetic models were used to analyze the reaction kinetics. The pseudo-second order kinetic model was found to be the best with good correlation. The decolorization reaction rate constants ($k_2$) of methylene blue were relatively higher than those of methyl orange and eriochrome black T. The reaction rate constants of methyl orange and eriochrome black T increased with a decrease in the initial pH.

• Journal of Electrochemical Science and Technology
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• 제12권1호
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• pp.82-91
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• 2021

This study was conducted to investigate the effect of initial pH, current density, and electrolysis time on process performance in terms of decolorization and chemical oxygen demand (COD) removal from disperse dyebath wastewater (DDW) by mono-polar parallel laboratory scale electrocoagulation (EC) process. COD reduction of 51.3% and decolorization of 92.8% were obtained with operating cost of 0.19 €/㎥ treated wastewater for Al-Al electrode pair, while 90.5% of decolorization and 49.2% of COD reduction were obtained with operating cost of 0.20 €/㎥ treated wastewater for an Fe-Fe electrode pair. The amount of sludge production were highly related to type of the electrode materials. At the optimum conditions, the amount of sludge produced were 0.18 kg/㎥ and 0.28 kg/㎥ for Al-Al and Fe-Fe electrode pairs, respectively. High decolorization can be explained by the hydrophobic nature of the disperse dye, while limited COD removal was observed due to the high dissolved organic matter of the DDW based on auxiliary chemicals. Energy, electrode, and chemical consumptions and sludge handling were considered as major cost items to find a cost-effective and sustainable solution for EC. The contribution of each cost items on operating cost were determined as 10.0%, 51.1%, 30.5% and 8.4% for Al-Al, and they were also determined as 9.0%, 38.0%, 40.5% and 12.5% for Fe-Fe, respectively. COD reduction and decolorization were fitted to first-order kinetic rule.

• 대한환경공학회지
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• 제28권7호
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• pp.738-745
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• 2006

본 연구에서는 염색폐수의 색도제거 기전을 미생물 floc에의 물리 화학적 흡착과 미생물의 대사에 의한 생물학적 제거의 두 가지로 분류하였다. 색도제거의 반응 조건, 즉 혐기/호기 조건, cosubstrate의 종류와 주입량 등을 회분식 실험에 의해 규명하고, 활성슬러지와 비활성슬러지의 biosorption 실험을 통하여 색도제거 기전을 확인하였다. 염색폐수의 색도는 호기조건과 혐기조건에서 각각 102 ${\Delta}$unit/g MLSS, 123 ${\Delta}$unit/g MLSS가 제거되어 혐기조건에서의 제거율이 높았으며, 유기물은 호기조건에서 82 $mg{\Delta}$COD/gMLSS, 혐기조건에서 75 $mg{\Delta}$COD/gMLSS 제거되어 호기조건에서 제거율이 더 높게 나타났다. Cosubstrate로서 실폐수인 가정하수와 acetate를 이용하여 주입량에 따른 염색폐수의 제거능을 분석한 결과, cosubsrate의 주입에 따라 색도 및 유기물 제거량이 증가함을 확인하였으며 가정하수보다는 acetate가 색도제거에 있어서 더 효율적인 cosubstrate임을 알 수 있었다. 활성슬러지와 멸균된 비활성슬러지를 이용한 색도제거 실험 결과. 비활성슬러지의 색도제거량은 가정하수의 주입에 따라 $20.3{\sim}37.3$ ${\Delta}$unit/g MLSS, 활성슬러지는 $102.0{\sim}159.0$ ${\Delta}$unit/g MLSS로 나타났다. 또한 반응 초기에는 물리 화학적 흡착이 우세하였으나 시간이 지나면서 생물대사 작용에 의한 제거가 증가하는 경향을 보였으며, cosubstrate의 주입에 따른 미생물의 대사에 의한 제거분율이 증가하는 것으로 분석되었고, 이는 호흡율 측정결과와도 그 경향이 일치하였다.