• Journal of Electrochemical Science and Technology
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• 제14권2호
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• pp.174-183
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• 2023

The dye wastewater discharge from the textile industries mainly affects the aquatic environment. Hence, the treatment of this wastewater is essential for a pollutant-free environment. The purpose of this research is to optimize the dye removal efficiency for process influencing independent variables such as pH, electrolysis time (ET), and current density (CD) by using Box-Behnken design (BBD) optimization and Genetic Algorithm (GA) modelling. The electrocoagulation treatment technique was used to treat the synthetically prepared Reactive Black dye solution under batch mode potentiometric operations. The percentage of error for the BBD optimization was significantly greater than for the GA modelling results. The optimum factors determined by GA modelling were CD-59.11 mA/cm², ET-24.17 minutes, and pH-8.4. At this moment, the experimental and predicted dye removal efficiencies were found to be 96.25% and 98.26%, respectively. The most and least predominant factors found by the beta coefficient were ET and pH respectively. The outcome of this research shows GA modeling is a better tool for predicting dye removal efficiencies as well as process influencing factors.

• Advances in environmental research
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• 제9권2호
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• pp.135-150
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• 2020

Many industries, such as textiles, chemical refineries, leather, plastics and paper, use different dyes in various process steps. At the same time, these industrial sectors are responsible for discharging contaminants that are harmful and toxic to humans and microorganisms by introducing synthetic dyes into wastewater. Of these dyes, methylene blue dye, which is classified as basic dyes, is accepted as a model dye. For this reason, methylene blue dye was selected in the study and its removal from the water was studied. In this study, two efficient biosorbents were developed from chitosan and sunflower waste, an agro-industrial waste and modified using iron nanoparticles. The biosorption efficiency was evaluated for methylene blue (MB) dye removal from aqueous solution under various parameters such as treating agent, solution pH, biosorbent dosage, contact time, initial dye concentration and temperature. We investigated the kinetic properties of dye removal from water for Chitosan-Sunflower (CS), Chitosan-Sunflower-Nanoiron (CSN). When the wavelength of MB dye was spectrophotometrically scanned, the maximum absorbance was determined as 660 nm. For the core shell biosorbents we obtained, we found that the optimum time for removal of MB from wastewater was 60 min. The pH of the best pH was determined as 5 in the studied pH. The most suitable temperature for the experiment was determined as 30℃. SEM-EDAX, TEM, XRD, and FTIR techniques were used to characterize biosorbents produced and modified in the experimental stage and to monitor the change of biosorbent after dye removal. The interactions of the paint with the surface used for removal were explained by these techniques. It was calculated that 80% of CS and 88% of CSN removed MB in optimum conditions. Also, the absorption of MB dye onto the surface was investigated by Langmiur and Frendlinch isotherms and it was determined from the results that the removal was more compatible with Langmiur isotherm.

• Journal of Industrial and Engineering Chemistry
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• 제67권
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• pp.175-186
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• 2018

Carbon nanomaterials (CNMs), particularly carbon nanotube and graphene-based materials, are rapidly emerging as one of the most effective adsorbents for wastewater treatment. CNMs hold great potential as new generation adsorbents due to their high surface to volume ratio, as well as extraordinary chemical, mechanical and thermal stabilities. However, implementation of pristine CNMs in real world applications are still hindered due to their poor solubility in most solvents. Hence, surface modification of CNMs is essential for wastewater treatment application in order to improve its solubility, chemical stability, fouling resistance and efficiency. Numerous studies have reported the applications of functionalized CNMs as very promising adsorbents for treating organic and inorganic wastewater pollutants. In this paper, the removal of organic dye and phenol contaminants from wastewater using various type of functionalized CNMs are highlighted and summarized. Challenges and future opportunities for application of these CNMs as adsorbents in sustainable wastewater treatment are also addressed in this paper.

• 한국지반환경공학회 논문집
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• 제7권3호
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• pp.21-29
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• 2006

난분해성 염색폐수를 처리하기 위한 화학적 처리 방법으로 오존단독처리와 3가지 경우의 고도산화공정[AOPs($O_3/H_2O_2$, $O_3/UV$, $O_3/H_2O_2/UV$)]의 처리특성을 실험적으로 검토하였다. 각각의 처리방법에서 합성 염색폐수를 대상으로 $COD_{cr}$ 및 색도의 제거효율, 생분해도(biodegradability)향상에 대한 처리특성을 상대적으로 비교 평가하였고 pH, 온도, 주입량, 순환유량 등을 주요운전인자로 하여 각 산화공정의 최적운전 조건을 파악하였다. 대상으로 한 모든 공정에서 염색폐수의 색도는 단시간에 대부분 제거되었지만, $COD_{cr}$ 제거측면과 생분해도 향상에서는 $O_3/H_2O_2/UV$ 공정이 가장 좋은 처리효율을 나타냈다.

• KSBB Journal
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• 제14권6호
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• pp.731-736
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• 1999

동두천과 반월공단에서 87가지의 균주를 분리하였다. 그 중 5가지 균주가 색도 제거율이 우수함을 보였으며, 동정을 통해 Shewanella putrefaciens, Aeromonas salmonicida(서로 다른 3종), Pseudomonas vesicularis로 각각 동정되었다. 동정된 5종의 미생물들은 성장에 최적인 pH와 온도는 각각 7.0과 30$^{\circ}C$이었으며, Gram negative, catalase nagative, rod shape, 그리고 비운동성을 보였다. 500 mL 플라스크에서 분리된 균주 중 단일균주를 사용하여 염색폐수를 처리한 경우 약 35%의색도 제거율을 보였다. 2균주를 조합하여 적용하였을 때는, 색도 제거율이 65%까지 증가한 반면, 3균주 조합 혹은 그 이상의 균주 조합에서는 2균주 조합보다 더 좋은 효율은 보이지 않았다. 염색폐수 분해시 $Mn^{2+},\;Fe^{3+}$와 같은 중금속의 영향을 조사하였는데, 70 ppm 이하의 농도에서는 별로 영향을 주지 않았다.

• 공업화학
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• 제24권5호
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• pp.544-550
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• 2013

본 연구에서는 소수성 다공질 세라믹관이 결합된 수중 유전체장벽방전 플라즈마 반응기를 이용하여 모사 염색폐수의 색도저감을 조사하였다. 플라즈마에 의해 생성되는 활성성분들은 수명이 매우 짧으므로 생성되는 즉시 물과 접촉시켜야 효과적인 폐수처리가 가능하며, 또한 반응속도를 증가시키기 위해서는 기/액 접촉면적이 커야 하는데, 본 연구의 반응기는 두 가지 목적을 동시에 이룰 수 있다. 아조 염료로는 amaranth, 그리고 플라즈마 생성을 위한 기체로는 공기가 사용되었으며, 방전전력, 기체 유량, 용존 음이온, 염료 초기농도 등 색도 제거에 미치는 다양한 변수의 영향이 평가되었다. 기체유량이 $1.5Lmin^{-1}$일 때, 플라즈마 기체가 염색폐수와 가장 효과적으로 접촉하였으며, 색도 제거가 가장 빠르게 일어났다. 염료 초기농도 $40.2{\mu}molL^{-1}$ (폐수부피 : 0.8 L), 방전전력 3.37 W의 조건에서 색도를 99% 이상 제거하는데 약 25 min이 소요되었다. 그밖에 염료의 초기농도가 낮을수록, 방전전력이 높을수록 색도 제거 속도가 증가하는 것으로 나타났다. 염소이온이 존재할 경우 색도 제거 속도가 빨라졌으나, 질산이온은 색도 제거 속도에 영향을 주지 않았다.

• Advances in environmental research
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• 제6권1호
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• pp.1-14
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• 2017

New technologies or improvement of the existing technologies are required to enhance the efficiency of removal of pollutants from wastewater. In this study we attempted to produce and test the activated carbon produced from the refused tea waste for the removal of dyes from wastewater. The objectives of this investigation were to produce activated carbon from refused tea waste by chemical activation, evaluate its performance for the removal of color produced from Acid Yellow 36, and the modeling of its dye removal with the kinetic study. The activation was performed in two steps namely carbonization at $375{\pm}25^{\circ}C$ and chemical activation with HCl at $800^{\circ}C$ under the absence of Oxygen. Adsorption isotherms and kinetic studies were performed with a textile dye, Acid Yellow 36, at different concentrations (20-80 mg/L). The maximum dye removal (~90%) observed at 80 mg/L dye concentration and it reduced at low dye concentrations. Maximum adsorption (71.97 mg/g) was recorded at 96 h at $29{\pm}1^{\circ}C$. Low pH increased the dye adsorption (pH=2; 78.27 mg/g) while adsorption reduced at high pH levels indicating that the competition occurs in between OH- ions and AY36 molecules for the adsorption sites in RTAC. The Langmuir isotherm model clearly explained the dye adsorption, favorably, by RTAC. Moreover, kinetic studied performed showed that the pseudo second order kinetic model clearly describes the dye adsorption. Based on the results obtained in this study, it can be concluded that RTAC can be used for the removal of textile dyes.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XIII)
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• pp.398-401
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• 2003

Azo dyes are aromatic compounds characterized by one or more azo bonds $(R_l-N=N-R_2)$. More than 800,000 tons of dyes are produced annually worldwide, of which 60-70% are azo dyes. During manufacturing, an estimated 10-15% is released into the environment. Aside from their negative aesthetic effects, certain azo dyes have been shown to be toxic and, in some cases, these compounds are carcinogenic and mutagenic. To establish biological wastewater treatment of azo dye, it is essential to discover azo dye-degrading microorganisms. In this report, sludge-contaminated with dyes were gathered through wastewater outlets from the industrial regions. The following to separation of bacteria within them, bacteria which decolorize methyl red, a azo dye, were selected and destined.

• The Korean Journal of Ecology
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• 제16권1호
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• pp.51-61
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• 1993

Crystal violet, a typical triphenylmenthane dye (N, N, N', N', N", N"-hexa methylparaosaniline), extensively used in textile dye, industry and research, has been suggested to cause tumor growth in botton-feeding fishes. For the isolation of crystal violet degrading bacteria, wastewaters were sampled from plants' wastewater treatment facility, textile treatment facility, textile wastewater treatment plant and etc.. The most efficient strain in crystal violet degrading bacteria was identified as Klebsiella oxytoca. Added sole carbon source in PAS minimal media was 10mg/l crystal violet, which incubated at 30。C, the degrading efficiency was maximum 12.3%. When fructose, glucose, sucrose and yeast-extract were added 0.01% in PAS media respectively, the degrading efficiency were all 96% within 24 hours.

• Applied Biological Chemistry
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• 제38권5호
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• pp.452-454
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• 1995

게 껍질과 갑오징어 널에서 조제한 키틴과 키토산을 흡착제로 사용하여 염색공장에서 폐기되는 폐색소를 정화하기 위한 실험을 수행하였다. 이중 키토산이 키틴 보다 효율적인 흡착제로 작용하였으며, 키토산을 채운 컬럼 실험에서 1kg의 키토산은 0.05%의 색소를 함유한 염색 폐수 120L를 75% 효율로 흡착제거하였다. 이는 1kg의 키토산이 45g의 색소를 흡착하였다는 것을 의미한다.