• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2005년도 춘계학술발표논문집
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• pp.274-276
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• 2005

본 논문에서는 유동층 화학기상증착법(FB CVB; Fluidized Bed Chemical Vapor Deposition)으로 광촉매가 박막증착된 비드를 제조하였고 제조된 광촉매코팅비드의 광반응성을 연속식 반응기에서 아세트알데히드의 분해능력을 측정하여 분석하였다. 광촉매가 박막증착된 비드의 FE-SEM 분석 결과 글라스 비드 위의 티타니아는 비교적 매끄럽게 증착되었고, 실리카 위의 티타니아는 입자의 형태로 증착되었으며 알루미나 위의 티타니아는 결정상을 이루며 증착됨을 확인 할 수 있었다. Acetaldehyde 기체의 광촉매에 의한 분해 실험을 진행하기 위해 연속식 반응기를 설계 제작하였고, 이 반응기를 사용하여 제조된 광촉매 코팅입자의 광반응성을 살펴보았다. 반응기는 가스 주입구와 출구를 갖고 있으며, 중심부에 UV 램프가 설치되었다. 반응기는 내열유리(pyrex)로 제작하였으며, 체적은 100 ml이다. 반응기 내부의 중심부에 UV 램프가 설치되고 UV 램프와 반응기 외부사이에 유동층 화학기상증착법에 의해 티타니아가 박막증착된 광촉매입자가 위치하여 광반응성을 평가하였다. 유량변화에 따른 광반응성을 측정하였으며, 알루미나에 광촉매를 증착시킨 제품의 경우 가스유량 100cc/min에서는 acetaldehyde가 $100\%$ 분해되고, 가스유량 500cc/min에서는 $50\%$정도 분해되는 것을 알 수 있었다.

• 한국환경과학회지
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• 제22권7호
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• pp.915-923
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• 2013

Decomposition of non-biodegradable contaminants such as phenol contained in water was investigated using a dielectric barrier discharge (DBD) plasma reactor in the aqueous solutions with continuous oxygen bubbling. Effects of various parameters on the removal of phenol in aqueous solution with high-voltage streamer discharge plasma are studied. In order to choose plasma gas, gas of three types (argon, air, oxygen) were investigated. After the selection of gas, effects of 1st voltage (80 ~ 220 V), oxygen flow rate (2 ~ 7 L/min), pH (3 ~ 11), and initial phenol concentration (12.5 ~ 100.0 mg/L) on phenol degradation and change of $UV_{254}$ absorbance were investigated. Absorbance of $UV_{254}$ can be used as an indirect indicator of phenol degradation and the generation and disappearance of the non-biodegradable organic compounds. Removal of phenol and COD were found to follow pseudo first-order kinetics. The removal rate constants for phenol and COD of phenol were $5.204{\times}10^{-1}min^{-1}$ and $3.26{\times}10^{-2}min^{-1}$, respectively.

• 한국분말재료학회지
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• 제25권2호
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• pp.132-136
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• 2018

Core/shell CdSe/ZnS quantum dots (QDs) are synthesized by a microfluidic reactor-assisted continuous reactor system. Photoluminescence and absorbance of synthesized CdSe/ZnS core/shell QDs are investigated by fluorescence spectrophotometry and online UV-Vis spectrometry. Three reaction conditions, namely; the shell coating reaction temperature, the shell coating reaction time, and the ZnS/CdSe precursor volume ratio, are combined in the synthesis process. The quantum yield of the synthesized CdSe QDs is determined for each condition. CdSe/ZnS QDs with a higher quantum yield are obtained compared to the discontinuous microfluidic reactor synthesis system. The maximum quantum efficiency is 98.3% when the reaction temperature, reaction time, and ZnS/CdSe ratio are $270^{\circ}C$, 10 s, and 0.05, respectively. Obtained results indicate that a continuous synthesis of the Core/shell CdSe/ZnS QDs with a high quantum efficiency could be achieved by isolating the reaction from the external environment.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XIII)
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• pp.463-467
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• 2003

Fundamental experiments were carried out about color removal efficiency of dyeing wastewater using a $bioreactor-TiO_2/UV$ reactor system. Color removal efficiencies of the Reactive Black 5 in the system were found to bo more than 80% in changes of dilution rate 0.04 to $0.08hr^{-1}$. In this research, a new color removal system of dying wastewater will be proposed after more investigation of decolorization efficiencies about different dyes and condition.

• 한국막학회:학술대회논문집
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• 한국막학회 1992년도 추계 총회 및 학술발표회
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• pp.9-9
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• 1992

막 반응기(membrane reactor)는 365 nm 의 파장을 갖는 UV를 담체튜브 및 코팅막에 조사시켜 막 표면에서 유기물의 산화반응이 일어날수 있도록 고안하였으며 일차적으로 formic acid의 산화효율을 측정하였다. 코팅된 담체는 코팅하지 않은 담체에 비해 flux가 상당히 저하하는 반면에 formic acid의 산화효율은 이에 비례하여 증가하였다. 또한 본 실험의 결과로부터 수처리공정에서 문제시되는 난분해성 유기물질의 산화분해처리에 대한 광촉매 막의 응용성을 제시하고자 한다.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 1999년도 추계 학술발표회 논문집
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• pp.67-70
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• 1999

최근에 들어서 태양에너지의 화학적 에너지로의 변환에 대한 연구는 에너지 부족에 대한 대안으로서 각광을 받고 있는 분야이다. 이런 관심을 바탕으로 한 다양한 연구는 연속식 또는 회분식 반응기를 이용한 불균일계 촉매를 이용함으로써 진행되고 있고, 특히 기-액, 기-고 그리고 기-액-고상 반응기를 응용하는 광촉매 반응에 관심이 증폭되고 있다. 그리고 광촉매 반응이 실제 산업계에서 활용되기 전에 먼저 불균일계 광촉매 반응기의 설계기준에 대한 연구가 선행되어야 하며 실제 산업적인 응용측면에서도 광촉매 반응의 충분한 이용가능성에 관심이 이루어져야 한다.(중략)

• 한국환경보건학회지
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• 제37권3호
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• pp.218-225
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• 2011

Objectives: In this paper, a dielectric barrier discharge (DBD) plasma reactor was investigated for degrading the dye Rhodamine B (RhB) in aqueous solutions. Methods: The DBD plasma reactor system in this study consisted of a plasma component [titanium discharge (inner), ground (outer) electrode and quartz dielectric tube], power source, and gas supply. The effects of various parameters such as first voltage (input power), gas flow rate, second voltage (output power), conductivity and pH were investigated. Results: Experimental results showed that a 99% aqueous solution of 20 mg/l Rhodamine B is decolorized following an eleven minute plasma treatment. When comparing the performance of electrolysis and plasma treatment, the RhB degradation of the plasma process was higher that of the electrolysis. The optimum first voltage and air flow rate were 160 V (voltage of trans is 15 kV) and 3 l/min, respectively. With increased second voltage (4 kV to 15 kV), RhB degradation was increased. The higher the pH and the lower conductivity, the more Rhodamine B degradation was observed. Conclusions: OH radical generation of dielectric plasma process was identified by degradation of N, N-dimethyl-4-nitrosoaniline (RNO, indicator of OH radical generation). It was observed that the effect of UV light, which was generated as streamer discharge, on Rhodamine B degradation was not high. Rhodamine B removal was influenced by real second voltage regardless of initial first and second voltage. The effects of pH and conductivity were not high on the Rhodamine B degradation.

• Environmental Engineering Research
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• 제21권4호
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• pp.384-392
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• 2016

The aim of this study was to investigate the removal efficiency of $17{\alpha}$-methyltestosterone (MT) from aqueous solution by Salvinia cucullata Roxb. ex Bory in an active plant-based reactor with a specific focus on linear regression analysis for the sorption phenomena of MT onto the plant roots. A high performance liquid chromatographic method using UV detection (245 nm) was used to analyse the samples. The batch experiments of the active plant reactor (APR) were established to investigate the ability of Salvinia cucullata to remove MT from the liquid phase. The results revealed that 40% and 60% removal of MT from the liquid phase was observed at 5 min. and at 4 h, respectively. Salvinia cucullata can effectively remove MT from the aqueous solution in APRs. Kinetic studies revealed that the sorption phenomena of MT by Salvinia is best described using a linearized pseudo - second order model. Based on the kinetic parameters, it is likely that during the first 4 h of the contact (t = 0 to t = 4 h) sorption is the major driving mechanism of the disappearance of MT from aqueous solutions. However, at higher MT concentrations, diffusivity of MT has a significant effect on the migration of MT from the bulk stream to the root surface. The isotherm analysis revealed that the sorption kinetics favourably followed pseudo second-order. The results of isotherm analysis have indicated that the sorption of MT onto the root surfaces of Salvinia cucullata was favourable and almost irreversible.

• 한국환경보건학회지
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• 제29권1호
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• pp.51-61
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• 2003

Pollution purification using titanium dioxide (TiO$_2$) photocatalyst has attracted a great deal of attention with increasing number of relent environmental problems. Currently, the application of TiO$_2$ photocatalyst has been focused on purification and treatment of waste water. However. the use of conventional TiO$_2$ powder photocatalyst results in disadvantage of stirring during the reaction and of separation after the reaction. And the usage of artificial UV lamp has made the cost of photocatalyst treatment system high. Consequently, we herein studied the pilot-scale design to aid in optimization of the energy-saving process for more through development and reactor design by solar light/UV lamp/ TiO$_2$system. In this study, we manufactured the TiO$_2$sol by sol-gel method. According to analysis by XRD, SEM and TEM, characterization of TiO$_2$ sol were nano-size (5-6 nm) and anatase type. Inorganic binder (SiO$_2$) was added to TiO$_2$ lot to be coated for support strongly, and support of ceramic bead was used to lower separation rate that of glass bead The influences were studied of various experimental parameters such as TiO$_2$ quantity, pH, flow rate. additives, pollutants concentration, climate condition and reflection plate by means of reaction time of the main chararteristics of the obtained materials. In water treatment system, variable realtor as solar light/ or UV lamp according to climate condition such as sunny and cloudy days treated the phenol and E-coli(Escherichia coli) effectively.

• Korean Chemical Engineering Research
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• 제50권1호
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• pp.11-17
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• 2012

졸-겔 방법에 의하여 제조된 $TiO_2$와 $TiO_2-SiO_2$ 광촉매를 이용한 음용수 중의 대장균 살균과 엔도톡신 제거에 관한 연구를 수행하였다. 대장균 살균실험은 대장균이 포함된 물이 순환되는 annular-흐름식 광촉매 코팅 반응기에서 수행되었다. 대장균의 살균능은 $TiO_2$와 $TiO_2-SiO_2$ 광촉매의 아나타제 결정성피크의 세기와 비례하였다. UV-A 조사하에 $TiO_2$가 코팅된 반응기에서 2시간 내에 대장균을 100% 살균시킬 수 있었으며, 대장균 사멸시 생성되는 독성물질인 엔도톡신이 존재하지 않았다. 그러나 UV-C 조사하에서는 30분 이내에 대장균을 100% 살균할 수 있었으나 엔도톡신이 완전히 제게되지 않았다. 따라서 광촉매와 UV-A 조사가 음용수 살균에 유용함을 알 수 있었다.