• Membrane and Water Treatment
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• 제11권2호
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• pp.123-130
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• 2020

Submerged Membrane bioreactor (SMBR) is one of the last techniques that allow a high quality of treated industrial effluents by coupling biological treatment and membrane separation. Thus, this research was an effort to evaluate performance of a SMBR treating a model textile wastewater (MTWW). Different SMBR operating parameters like mixed liquor suspended solids (MLSS) and Dissolved oxygen concentration, hydraulic retention time (HRT), and nutrients addition (N and P) have been investigated. MTWW (influent to the SMBR) was generated using the reactive azo-dye, Novacron blue FNG (100mg/L feed concentration). Results of MTWW treatment using SMBR under optimal operating conditions (MLSS, 4.2-13.3g/L; HRT, 4 days; pH, 6.9-7.2; conductivity, 400-900 μS/cm and temperature, 19.4-22.2 ℃) showed that COD and blue colour treatment performances are between 94-98% and 30-80%, respectively. It is concluded that SMBR can be used in large scale textile wastewater treatment plants to improve effluent quality in order to meet effluent discharge standards.

• Environmental Engineering Research
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• 제25권4호
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• pp.571-578
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• 2020

In this work, a detailed study on the electrochemical degradation of an azo dye, Orange G is performed using a platinum electrode. Indeed, the influence of the dye concentration (50-150 mg/L), the pH of the medium and the density of the electric current is studied on the rate of discoloration, the rate of mineralization, the efficiency of the electric current and the energy consumption. The UV-visible spectra of OG plotted against the degradation time show the decrease of the intensity of the characteristic dye peaks. In an environment rich in chlorides, all peaks disappear after 15 min of degradation. However, the peaks at wavelengths of 200 and 290 nm appeared after one hour of treatment. In K₂SO₄, the eliminated percentages are respectively 46, 54 and 61% for wavelengths of 245, 330 and 480 nm. This suggests that the degradation mechanisms in K₂SO₄ and KCl environments are not the same. In the middle rich in chlorides, the eliminated percentage of OG did not seem to be affected by the concentrations increase. These results confirm the hypothesis that electrochemical oxidation process is very favorable for concentrated pollutants discharge.

• 청정기술
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• 제10권3호
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• pp.131-137
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• 2004

오래 전부터 생물학적 폐수처리 방법에 대한 다양한 연구들이 꾸준히 진행되고 있으나, 전통적인 염료 염색 폐수처리 방법들은 다소 비효율적이다. 최근 들어 이를 극복하기 위하여 특정 미생물이나 효소를 이용한 연구들이 활발히 진행되고 있다. 본 연구에서는 백색부후균이 생산하는 리그닌 효소에 의한 생물처리 방법으로, 아조계(azo) 염료인 Reactive black 5를 적용하였으며, 다양한 농도에 따른 분해경향을 확인하였다. 미생물 재이용과 장기간 운전, 효율적인 유기물 제거의 가능성을 확인하기 위해 i)생물학적 처리와 ii)분리막 처리공정과 iii)이 두 가지를 결합한 공정의 처리 효율을 비교하였다. 결합공정을 사용하였을 때 색도제거율이 100%였으며, 총유기물(TOC) 제거율은 70% 이상으로 각 단위공정만으로 처리하였을 때보다 더 효율적인 결과를 보였다. 또한, 생물반응에서 배양말기까지 유지된 효소활성(40 U/ml laccase and 300-600 U/ml MnP)을 통해 미생물 재이용의 가능성을 확인하였다.

• Bulletin of the Korean Chemical Society
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• 제25권2호
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• pp.213-215
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• 2004

An indirect, sensitive and accurate method for the determination of trace amounts of hydrazine is described. The method is based on the oxidation of hydrazine by a known excess of iodate in the presence of hydrochloric acid. The unreacted iodate is used in the oxidation of hydroxylamine to nitrite. Sulfanilic acid is diazotized by the nitrite formed. The resulting diazonium ion is coupled with N-(1-naphthyl)ethylenediamine to form a stable azo dye, which shows an absorption maximum at 540 nm. Hydrazine can be determined in the range of 20-400 ng $mL^{-1}$ with a detection limit of 3.1 ng $mL^{-1}$. The relative standard deviation for 50, 200 and 400 ng $mL^{-1}$ of hydrazine is 2, 1.5 and 1.3%, respectively (n = 10). The method was applied to the determination of hydrazine in water samples.

• 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.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2006년도 임시총회 및 추계학술발표회
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• pp.44-46
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• 2006

• 한국염색가공학회지
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• 제13권6호
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• pp.381-390
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• 2001

The optimum carrier concentrations were obtained by the maxmium exhaustion ratios of polyester fabrics at 8$0^{\circ}C$ . The optimum concentrations of methylsalicylate, acetophenone, anisole, propiophenone, 2-ethyl hexyl alcohol, ethylene glycol and propylene glycol were $3g/\ell,\;12g/\ell,\;7g/\ell,\;5g/\ell,\;3g/\ell,\;35g/\ell,\;and\;40g/\ell$, respectively Azo, anthraquinone, and quinoline disperse dyes were quite stable up to PH 10.3, but nitro disperse dye were severely hydrolyzed in alkaline dyeing. The tensile strength decreased with increasing dyebath pH because the polyester fabrics were easily decomposed by alkali. The reduction cleaning could be canceled in alkaline dyeing because the carriers were solved by alkali during dyeing.

• 한국염색가공학회지
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• 제13권6호
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• pp.23-23
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• 2001

The optimum carrier concentrations were obtained by the maxmium exhaustion ratios of polyester fabrics at 80℃. The optimum concentrations of methylsalicylate, acetophenone, anisole, propiophenone, 2-ethyl hexyl alcohol, ethylene glycol and propylene glycol were 3g/ℓ, 12g/ℓ, 7g/ℓ, 5g/ℓ, 3g/ℓ, 35g/ℓ, and 40g/ℓ, respectively. Azo, anthraquinone, and quinoline disperse dyes were quite stable up to pH 10.3, but nitro disperse dye were severely hydrolyzed in alkaline dyeing. The tensile strength decreased with increasing dyebath pH because the polyester fabrics were easily decomposed by alkali. The reduction cleaning could be canceled in alkaline dyeing because the carriers were solved by alkali during dyeing.

• 한국안전학회지
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• 제13권2호
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• pp.96-103
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• 1998

The treatment of the wastewater of Carmine-6B Process was studied using an electrochemical batch reactor with Pt-electrodes. The concentration of azo dye was exponentially decreased unto 6-37% residuum during 50 hr operations. The fractional conversion was not influenced by the initial pH value, but it was increased with increasing the rotating speed and/or temperature of the electrolyte. It was observed by the differential method of rate analysis that the rate of the oxidation reaction at anode was exponentially increased with increasing the cell voltage. The pH of the wastewater was changed from acid or alkali to neutral. The COD of the solution was increased at the beginning of the treatment, but it was decreased soon.

• 한국환경과학회지
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• 제11권9호
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• pp.961-969
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• 2002

This study was performed : 1) to establish the experimental analysis conditions for the sorption and desorption of toxic organic contaminants to/from the activated sludge, sediment, and clay, and 2) to determine the sorption and desorption equilibrium coefficients of some representative halogenated aliphatic compounds. Through the preliminary sorption test using Azo dye, a setting of quantitative experimental conditions to determine the sorption and desorption characteristics was decided as follows; equilibration time of 180 minutes, centrifuge for 15 minutes at 5000$\times$g, and 500mg/$\ell$ of TOC concentration. The sorption and desorption characteristics of halogenated aliphatic compounds onto activated sludge, sediment and clay could be described very well using the Freundlich isotherm. The preference of the average sorption capacity of the overall compounds showed in the sequence sediment 0.26mg/g, clay 0.23mg/g, and activated sludge 0.11 mg/g. The desorption rate of the sorbed compounds onto activated sludge, sediment and clay was approximately 89.8%, 35.3%, and 66.4%, respectively.