• Membrane and Water Treatment
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• 제7권5호
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• pp.463-476
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• 2016

In this study, application of polypropylene hollow fiber membrane contactors for $CO_2$ removal from water in liquid-liquid extraction (LLE) mode was simulated. For this purpose, a steady state 2D mathematical model was developed. In this model axial and radial diffusion was considered to $CO_2$ permeation through the hollow fibers. $CO_2$ laden water is fed at a constant flow rate into the lumen side, permeated through the pores of membrane and at the end of this process, $CO_2$ solution in the lumen side was extracted by means of aqueous diethanolamine (DEA) and chemical reaction. The simulation results were validated with the experimental data and it was found a good agreement between them, which confirmed the reliability of the proposed model. Both simulation and experimental results confirmed the reduction in the percentage of $CO_2$ removal by increment of feed flow rate.

• Bulletin of the Korean Chemical Society
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• 제34권3호
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• pp.783-787
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• 2013

The separation and capture process of carbon dioxide from power plants is garnering interest as a method to reduce greenhouse gas emissions. In this study, aqueous alkanolamine solutions were studied as absorbents for $CO_2$ capture. The solubility of $CO_2$ in aqueous alkanolamine solutions was investigated with a continuous stirred reactor at 313, 333 and 353 K. Also, the heat of absorption ($-{\Delta}H_{abs}$) between the absorbent and $CO_2$ molecules was measured with a differential reaction calorimeter (DRC) at 298 K. The solubility and heat of absorption were determined at slightly higher than atmospheric pressure. The enthalpies of $CO_2$ absorption in monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), and 2-amino-2-methyl-1-propanol (AMP) were 88.91, 70.44, 44.72, and 63.95, respectively. This investigation showed that the heat of absorption is directly related to the quantity of heat for absorbent regeneration, and is dependent on amine type and $CO_2$ loading.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2011년도 춘계학술논문집 1부
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• pp.310-313
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• 2011

본 논문에서는 지구온난화의 주요원인 중의 하나인 이산화탄소를 포집하기 위한 새로운 흡수제를 연구하였다. 액상 흡수법에서 가장 중요한 핵심 기술요소는 성능과 경제성면에서 우수한 흡수제를 개발하는 것이다. 흡수평형장치인 VLE(Vapor-Liquid Equilibrium)장치를 사용하여 신규흡수제의 이산화탄소 흡수능을 평가하고 특성을 알아봄으로써 신 흡수제를 개발하고자 하였다. 기존 아민흡수제인 MEA(monoethanolamine), DEA(diethanolamine)와 비교한 결과 아미노산염 흡수제의 경우 MEA (1.108), DEA (1.105)의 이산화탄소 흡수능보다 0.15～0.2 (mol $CO_2$/mol absorbent) 더 높은 흡수능과 2.5～3배 더 빠른 겉보기 속도를 나타내는 것을 확인하였다. 본 연구를 통하여 개발된 아미노산염 흡수제가 경제적인 이산화탄소 포집공정을 구현할 수 있는 가능성을 확인하였다.

• 한국초전도ㆍ저온공학회논문지
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• 제5권3호
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• pp.23-25
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• 2003

Effect of chemically modified precursor solution on YBCO coated conductor prepared by MOD-TFA method was investigated. YBCO thin films were deposited on (l00)-oriented single crystalline LaAlO$_3$ substrates by conventional MOD-TFA process. The microstructures of YBCO thin films contain maze-like patterns. The origin of this microstructure was delineated by compositional inhomogeneity during the pyrolysis process and it was shown that addition of diethanolamine (DEA) improve the microstructure of grown YBCO films. In addition, it was demonstrated that the chemical modification of precursor solution makes no harmful effect on biaxial texture of YBCO thin films.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제2권1호
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• pp.85-90
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• 1998

The reaction rate of $CO_2$ with 2-amino-2-methyl-1-propanol (AMP), MEA monoethanolamine(MEA) and diethanolamine (DEA) in aqueous solutions has been determined using a stirred vessel with a plane gas-liquid interface over a wide range of concentrations of amines at different temperatures. The results show that the overall reaction rate is first order with respect to both $CO_2$ and amine. The reaction rate constant varies with temperature according to the relationship which agrees with the experimental data. The proposed interpretation is that the kinetic rate determining step is a reaction of $CO_2$ with amine to form carbamic acid which is then totally and immediately ionized.

• 한국세라믹학회지
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• 제31권11호
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• pp.1315-1322
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• 1994

In this study, stable PbTiO3 coating solution was prepared using diethanolamine(DEA) complexing agent and deposited on indium-tin oxide(ITO) coated glass substrate. Prepared thin films were dense and crack-free. Perovskite-type PbTiO3 thin films could be obtained above 50$0^{\circ}C$, while the films heat-treated above $650^{\circ}C$ showed undesired properties due to interface reactions between films and substrates and warpage phenomena of substrates. Measured maximum dielectric constant and loss tangent were found to be 144 and 0.0163 at 1 kHz, 55$0^{\circ}C$ heat-treatment, respectively.

• 한국세라믹학회지
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• 제33권6호
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• pp.623-630
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• 1996

A Sol-gel derived ferroelectric PbTiO3 thin film was synthesized by using diethanolamine (DEA) as a comple-xing agent. Surface chemical analyses were examined in order to study the effect of heating temperature on the composition of thin film by EPMA and XPS. A rapid volatilization of lead was observed in the films fired at $700^{\circ}C$ or higher and the ratio of Pb:Ti was found to be 34:66. A depth profile by Ar+ showed that the Ar sputtering decreased Pb amount of inner part of the film resulting in Ti-rich phase near the surface of the film.

• 한국환경과학회지
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• 제2권1호
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• pp.85-90
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• 1993

The reaction rate of $CO_2$ with 2-amino-2-methyl-1-propanol (AMP), MEA monoethanolamine (MEA) and diethanolamine (DEA) in aqueous solutions has been determined using a stirred vessel with a plane gas-liquid interface over a wide range of concentrations of amines at different temperatures. The results show that the overall reaction rate is first order with respect to both $CO_2$ and amino. The reaction rate constant varies with temperature according to the relationship which agrees with the experimental data. The proposed interpretation is that the kinetic rate determining step is a reaction of $CO_2$ with amine to form carbamic acid which is then totally and immediately ionized.

• 에너지공학
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• 제28권4호
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• pp.8-12
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• 2019

Thermal amine scrubbing is the most advanced CO₂ capture technique but its largescale application is hindered due to the large heat requirement during solvent regeneration step. The addition of a solid metal oxide catalysts can optimize the CO₂ desorption rate and thus minimize the energy consumption. Herein, we evaluate the solvent regeneration performance of Monoethanolamine (MEA) and Diethanolamine (DEA) solvents without and with two metal oxide catalysts (TiO₂ and V₂O₅) within a temperature range of 40-86℃. The solvent regeneration performance was evaluated in terms of CO₂ desorption rate and overall amount of CO₂ desorbed during the experiments. Both catalysts improved the solvent regeneration performance by desorbing greater amounts of CO₂ with higher CO₂ desorption rates at low temperature. Improvements of 86% and 50% in the CO₂ desorption rate were made by the catalysts for MEA and DEA solvents, respectively. The total amount of the desorbed CO₂ also improved by 17% and 13% from MEA and DEA solvents, respectively. The metal oxide catalyst-aided regeneration of amine solutions can be a new approach to minimize the heat requirement during solvent regeneration and thus can remove a primary shortfall of this technology.

• Korean Chemical Engineering Research
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• 제50권1호
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• pp.135-140
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• 2012

반응열량계를 사용하여 1, 2, 3차 아민 수용액과 이산화탄소의 반응열을 각각 측정하였다. 이를 통해 MEA(monoethanolamine, 1차 아민), EAE(2-(ethylamino) ethanol, 2차 아민), MDEA (N-methyldiethanolamine, 3차 아민) 30 wt% 수용액이 $40^{\circ}C$에서 이산화탄소와 반응시 발생하는 반응열을 측정하고 이를 $CO_2$의 loading ratio에 따라 어떻게 변화하는지 평가하였다. 또한, 입체장애 구조를 가지는 AMP(2-amino-2-methyl-1-propanol, 1차 아민), DEA(diethanolamine, 2차 아민), TEA(triethanolamine, 3차 아민) 30 wt% 수용액의 반응열을 각각 측정하여 입체장애 구조가 반응열에 미치는 영향을 살펴보았다. 그 결과, 흡수제의 입체장애 유무와 관계없이 1차 > 2차 > 3차 아민 순으로 반응열이 증가함을 확인하였다. 그리고 입체장애 아민이 동일 차수의 비 입체장애 아민보다 상대적으로 반응열이 낮지만 그 차이는 크지 않음을 확인하였다.