• 한국세라믹학회지
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• 제46권3호
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• pp.263-270
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• 2009

The effect of photoelectrocatalytic (PEC) degradation for different dyes with the CNT/$TiO_2$ electrode was studied. The prepared electrode was characterized with surface properties, structural crystallinity, elemental identification, and PEC activity. The $N_2$ adsorption data showed that the composites had decreased surface area compared with the pristine CNT. This indicated the blocking of micropores on the surface of CNT, which was further supported by observation via FESEM. XRD patterns of the composites showed that the CNT/$TiO_2$ composite contained a mixing anatase and rutile phase. EDX spectra showed the presence of C, O and Ti peaks for all samples. The decomposition efifciency of the prepared electrode was evaluated by the PEC degradation of three dyes (methylene blue (MB), rhodamine B (RH.B), methyl orange (MO)). The variations of the FT-IR spectra and pH value of dye solutions were measured during the PEC system; it was found that the CNT/$TiO_2$ electrode has better PEC degradation for MB solution than that of RH.B and MO. The proposed degradation mechanism was present.

• 한국환경과학회지
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• 제15권1호
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• pp.67-75
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• 2006

The degradation of Rhodamine B (RhB) in water was investigated in laboratory-scale experiments, using five advanced oxidation Processes (AOPs) $UV/H_2O_2$, lenten, photo-lenten, $UV/TiO_2,\;UV/TiO_2/H_2O_2$. The photodegradation experiments were carried out in a fluidized bed photoreactor equipped with an immersed 32 W UV-C lamp as light source. initial decolorization rate and COD removal efficiency were evaluated and compared. The results obtained showed that the initial decolorization rate constant was quite different for each oxidation process. The relative order of decolorization was: photo-fenton > $UV/TiO_2/H_2O_2$ > fenton > $UV/H_2O_2$ > $UV/TiO_2$ > UV > $H_2O_2$. The relative order of COD removal was different from decolorization: photo-fenten ${\fallingdotseq}$ $UV/TiO_2/H_2O_2\;>\;UV/TiO_2\;>\;fenton\;>\;UV/H_2O_2$. The Photo-lenten and $UV/TiO_2/H_2O_2$ processes seem to be appropriate for decolorization and COD removal of dye wastewater.

• 미생물학회지
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• 제55권1호
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• pp.83-85
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• 2019

남극 연안 툰드라 토양에서 리그닌 분해능이 있는 Pseudomonas sp. PAMC 29040를 분리하였으며, 이후 토양 유기물의 주요 구성성분인 복합유기화합물 부식질 분해능을 확인하였다. 부식질 초기 저분자화 효소(예, dye-decolorizing peroxidase)와 부식질 유래의 다양한 저분자 분해산물들을 분해하는 효소들(예, vanillate O-demethylase)를 탐색하기 위해 PAMC 29040 게놈 염기서열을 분석하였다. 분석을 통해서 최종 확보한 효소유전자 정보는 저온환경에 서식하는 토양 세균의 부식질 분해경로 제안에 활용될 것이다.

• 미생물학회지
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• 제55권2호
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• pp.177-179
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• 2019

미국 뉴저지주 중위도 산림토양에서 부식산(천연 복합유기화합물인 부식질의 주요 구성성분) 분해능이 있는 세균 균주 Pseudomonas kribbensis CHA-19를 분리하였으며, 이후 또 다른 토양 유기물인 리그닌과 리그닌 유래의 페룰산(ferulic acid)과 바릴린산(vanillic acid)의 분해능을 확인하였다. 부식질 초기 저분자화 효소(예, dye-decolorizing peroxidase와 laccase-like multicopper oxidase)와 부식질 유래의 다양한 저분자 분해산물들을 분해하는 효소(예, vanillate O-demethylase와 biphenyl 2,3-dioxygenase)를 탐색하기 위해 CHA-19 게놈염기서열을 분석하였다. 최종 확보한 효소유전자 정보는 토양세균의 부식질 분해경로 제안에 사용되었다.

• KSBB Journal
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• 제8권2호
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• pp.150-155
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• 1993

난분해성인 색소를 대사분해할 수 있는 미생물을 분리하여, 색소분해의 최적조건을 조사하였다. 미생물은 폐수처리공장의 폭기조에서 채취한 폐수로부터 agar media에서 순수분리하였다. 이 균주들을 glu­c cose, peptone, $Na_2HPO_45, KCI, MgSO_4, KH_2PO_4, NaCI, CaCI_2$와 dye(azo계, reactive red계 ) lOppm 을 함유한 액체 배지에서 dye의 분해력이 강하였으 며, 이때의 최적 pH는 중성 또는 약알칼리성이고, 최적 온도는 $30^{\circ}C$ 전후이다. 이 조건에서 10ppm의 m mono-azo(Lot No. 180), di-azo(Lot No. 138), re­a active red(Lot No.2)는 약 2일에 거의 분해되었고, di-azo(Lot No. 151), reactive red(Lot No. 34, L Lot No. 00166)는 약 5일에 거의 분해되었고, 최적 배지조건하에서 산소의 영향은 D.O를 50%로 유지 시켰을 경우보다 혐기성 배양의 경우가 reactive d dye(Lot No.2)의 분해도가 훨씬 높았다.

• 멤브레인
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• 제32권1호
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• pp.33-42
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• 2022

성장하는 산업화는 심각한 수질 오염으로 이어진다. 폐수로 배출되는 약품과 섬유산업에서 나오는 유기배출물은 환경과 생명에게 악영향을 미친다. 항균치료에 사용되는 항생제가 폐수에 존재하면 인체에 매우 해로운 약제 내성균의 성장을 야기하게 된다. 섬유산업에서 사용되는 유기염료 분자의 제조에는 다양한 유기 저분자가 사용된다. 이러한 분자들은 인쇄 및 염색 산업의 폐수 배출물에 존재하여 분해가 잘 이루지지 않는다. 이러한 문제들을 해결하기 위해 광분해성 촉매를 분리막에 도입하고 폐수를 처리한다. 이 과정을 통해 유기 분자는 광분해되며 동시에 분해된 화합물들은 분리막을 통과하여 분리된다. 이산화티타늄(TiO₂)은 뛰어난 광촉매 역할을 하는 반도체이다. 다른 전이 금속 산화물과 화합물을 만들고 고분자 막에 도입하여 광촉매 능력을 증가시킨다. 본 총설에서는 광촉매성 분리막에 의한 염료 및 약물 분자의 분해에 대해 논의한다.

• 한국환경과학회지
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• 제20권10호
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• pp.1273-1284
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• 2011

The aim of this research was to evaluate the performance of insoluble electrode for the purpose of degradation of Rhodamine B (RhB) and oxidants generation [N,N-Dimethyl-4-nitrosoaniline (RNO, indicator of OH radical), $O_3$, $H_2O_2$, free Cl, $ClO_2$)]. Methods: Four kinds of electrodes were used for comparison: DSA (dimensional stable anode; Pt and JP202 electrode), Pb and boron doping diamond (BDD) electrode. The effect of applied current (0.5~2.5 A), electrolyte type (NaCl, KCl and $Na_2SO_4$) and electrolyte concentration (0.5~3.5 g/L) on the RNO degradation were evaluated. Experimental results showed that the order of RhB removal efficiency lie in: JP202 > Pb > BDD ${\fallingdotseq}$ > Pt. However, when concerned the electric power on maintaining current of 1 A during electrolysis reaction, the order of RhB removal efficiency was changed: JP202 > Pt ${\fallingdotseq}$ Pb > BDD. The total generated oxidants ($H_2O_2$, $O_3$, free Cl, $ClO_2$) concentration of 4 electrodes was Pt (6.04 mg/W) > JP202 (4.81 mg/W) > Pb (3.61 mg/W) > BDD (1.54 mg/W), respectively. JP202 electrode was the best electrode among 4 electrodes from the point of view of performance and energy consumption. Regardless of the type of electrode, RNO removal of NaCl and KCl (chlorine type electrolyte) were higher than that of the $Na_2SO_4$ (sulfuric type electrolyte) RNO removal. Except BDD electrode, RhB degradation and creation tendency of oxidants such as $H_2O_2$, $O_3$, free Cl and $ClO_2$, found that do not match. RNO degradation tendency were considered a simple way to decide the method which is simple it will be able to determinate the electrode where the organic matter decomposition performance is superior. As the added NaCl concentration was increases, the of hydrogen peroxide and ozone concentration increases, and this was thought to increase the quantity of OH radical.

• Elastomers and Composites
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• 제58권4호
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• pp.191-200
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• 2023

In this study, MoS₂ nanoparticles were synthesized and analyzed through powder X-ray diffraction, Raman, ultraviolet-visible, and X-ray photoelectron spectroscopies. The surface morphologies of the as-synthesized MoS₂ nanoparticles were investigated through scanning and transmission electron microscopies. The sonocatalytic activity of the MoS₂ nanoparticles toward Orange II removal was evaluated by utilizing a Box-Behnken design for response surface methodology in the experimental design. The sonocatalyst dosage, Orange II dye concentration, and ultrasound treatment time were optimized to be 0.49 g/L, 5 mg/L, and 150 min, respectively. The maximum efficiency of Orange II degradation on MoS₂ nanoparticles was achieved, with a final average value of 82.93%. Further, the results of a kinetics study on sonocatalytic Orange II degradation demonstrated that the process fits well with a pseudo-first-order kinetic model.

• Carbon letters
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• 제9권2호
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• pp.131-136
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• 2008

In order to investigate the effect of doping C, N, B and F elements on $TiO_2$ for reducing the band gap, the heat treatment of $TiO_2$ was carried out with tetraethylammonium tetrafluoroborate. Through XRD and XPS analysis, the C, N, B and F doped anatase $TiO_2$ was confirmed. According to the increase of temperature during treatment, the particle size was increased due to aggregation of $TiO_2$ with elements (B, C, N and F). To investigate the capacity of photocatalyst for degradation of dye under solar light, the degradation of acridine orange and methylene blue was conducted. The degradation of dyes was carried out successfully under solar light indicating the effect of doping elements (B, C, N and F) on $TiO_2$ for reducing the band gap effectively.

• 한국결정성장학회지
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• 제19권5호
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• pp.268-276
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• 2009

In this study, activated carbon (AC) was treated with ferric ion by a sol-gel method. The compound (Fe-AC) was employed for the preparation of Fe-activated carbon/$TiO_2$, (Fe-AC/$TiO_2$) composites. The prepared Fe-AC/$TiO_2$ composites were characterized with surface properties, structural crystallinity, elemental identification and photocatalytic activity. The SEM results showed that ferric compounds and titanium dioxide were fixed onto the AC surfaces. The XRD results showed that Fe-AC/$TiO_2$ composites mostly contained anatase phase. EDX showed the presence of C, O, and Ti with Fe peaks in all samples. Its photocatalytic degradation effect was evaluated with the degradation behavior of the methylene blue (MB) solution. MB degradation could be attributed to the synergetic effects of adsorption, photo-degradation of $TiO_2$ and photo-Fenton of Fe component. The degradation rate for this photocatalysis was evaluated as a function of the concentration of the dye, the amount of $TiO_2$ and the pH. Photocataytic activity is good at activity pH.