• Journal of Korea Foresty Energy
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• v.21 no.2
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• pp.25-33
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• 2002

One of the critical problems to preserve books and documents in libraries and archives is the deterioration. Some of previous results showed that the major cause of paper deterioration was the acid-catalyzed hydrolysis of the cellulose in paper fibres and aging rate of acidic paper was faster than that of alkaline paper. Therefore, It is necessary to remove the acid in the paper for reducing the rate of paper deterioration. It has been reported to extend the useful life of acidic paper by three to five times. Recently, It has been recognized the need for an effective method of deacidifying large quantities of books and document. However, in the previous many reports little attention was paid to the effect of paper additives. In this paper, We carried out experiment about the effect of additives on paper aging and the effect of deacidification by the gaseous ethanolamines (monoehtanolamine, diethanolamine, triehtanolamine). In result, it was found that the strength of aging was in the order of the alum＋rosin＞alum ＞AKD＞ control and the rate of deacidification was in the order of the monoethanolamine＞diethanolamine＞triethanolamine. The treatment with the gaseous ethanolamines caused decreasing of brightness and dropping of fold endurances. However, deacidification by combination treatment of the various gaseous ehtnaolamines prevented from decreasing of brightness and dropping of folding endurances.

• Proceeding of EDISON Challenge
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• 2014.03a
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• pp.53-61
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• 2014

온실가스 증가로 인한 지구온난화 문제가 범세계적인 문제로 대두되고 있는 가운데, 특히 온실가스 중 약 76%이상을 차지하는 이산화탄소를 흡수하기 위한 흡수제 개발에 여러 국가들이 심혈을 기울이고 있다. 그 중 이산화탄소 흡수제로 가장 상용화 되어 있는 모노에탄올아민(monoethanolamine, MEA)은 분자량이 작아 몰 농도비에 따른 이산화탄소의 흡수에 유리하고 반응속도가 빠르다는 장점이 있으나, 재생에 필요한 에너지가 높다는 단점이 존재한다. 수용액중에서 MEA가 $CO_2$를 흡수하는 반응의 반응자유에너지는 반응메카니즘을 이해하는데 가장 기본적인 도구이다. 본 연구에서는 B3LYP, M06-2X의 밀도범함수를 이용하여 MEA의 $CO_2$ 흡수반응의 반응자유에너지를 계산하는 계산모델을 선정하였다. 수용액에서 MEA가 $CO_2$를 흡수하는 반응의 반응자유에너지를 밀도범함수를 이용하여 계산할 때는, 수용액상태에서 화학종의 분자구조를 최적화하는 것이 필요하였다. 또한 M06-2X 밀도범함수가 B3LYP 밀도범함수보다 좋은 결과를 주었으며, 분산보정을 하는 것이 보다 좋은 결과를 주었다.

• Korean Chemical Engineering Research
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• v.49 no.6
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• pp.764-768
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• 2011

The process of $CO_2$ capture using aqueous Monoethanolamine(MEA) has been considered as one of the leading technologies for intermediate-term strategy to reduce the $CO_2$ emission. This MEA process, however, consumes relatively a large amount of energy in the stripper for absorbent regeneration. For this reason, various process alternatives are recently established to reduce the regeneration energy. This paper suggests a flue gas split configuration as one of MEA process alternatives and then simulates this process using commercial simulator. This flue gas splitting has an effect on reducing the temperature of the lower section of absorber as well as decreasing the absorbent flow rate. Compared to the base model, this optimized flue gas split process provides 6.4% reduction of solvent flow rate and 5.8% reduction of absorbent regeneration energy.

• Clean Technology
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• v.14 no.2
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• pp.87-94
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• 2008

The catalytic properties of large pore zeolite (mordenite, beta, and Y) with 12-membered rings were comparatively evaluated in the synthesis of diethylamines from ethanol amination. The number of strong acid sites, which obviously promoted the formation of mono- and diethylamines, was decreased with the increase of Si/Al ratio of the zeolites that were used. H-beta and H-Y zeolites with multidimensional pore channels favorably formed diethylether by the dimerization of ethanol, due to their large cage volumes and low acid strength. On the other hand, H-mordenite which has one dimensional straight channel was shown to be suitable for the formation of mono- and diethylamine which are well known as the useful intermediates of fine chemicals.

• Journal of the Korean Applied Science and Technology
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• v.29 no.1
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• pp.88-94
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• 2012

In this study, the current-voltage curves for metals were measured using cyclic voltammetry. The relationship between the electrochemical properties and surface states of metals were investigated by Scanning Electron Microscope (SEM). In cyclic voltammetry, we used a 3-electrode system for the electrochemical measurements. The measurement was conducted at the condition that consists of the first reduction from the initial potential to -1350 mV, continuous oxidation to 1650 mV, and last reduction to the initial potential. The scan rates were 50, 100, 150 and 250 mV/s. The results show the C-V characteristics of metals to be for an irreversible process, which was caused by the oxidation current from cyclic voltammogram, when monoethanolamine (MEA) was used as a corrosion inhibitor. When we used MEA as a corrosion inhibitor, the diffusion coefficient was decreased as the concentration of electrolyte was increased. In the SEM images of copper, we observed an increase of surface corrosion at the increased electrolyte concentration. Addition of $1.0{\times}10^{-3}M$ corrosion inhibitor MEA reduced the effect of corrosion prevention due to the relatively large diffusion coefficient at the electrolyte concentration of 0.1N.

• Applied Chemistry for Engineering
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• v.21 no.2
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• pp.195-199
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• 2010

The reversible chemical absorption using MEA (monoethanolamine), one of alkanolamine, is generally used as a conventionally method for $CO_{2}$ capture. Even MEA absorbent has excellent reactivity with $CO_{2}$, it has been known to have the decrease of absorption capacity caused by $CO_{2}$, $O_{2}$ or other acid gases in flue gas, corrosion and thermal degradation. In this study, MEA solutions degraded in the steam reforming process of refinery used and the absorption performance were compared for the used of conventional MEA solution. In case of 30 wt% MEA and mixture of 20 wt% thermal degraded absorbent (DP) and 10 wt% PZ, the absorption capacities were $0.5365mol-CO_{2}$/mol-absorbent and $0.5939mol-CO_{2}$/mol-absorbent respectively. PZ added thermally degraded absorbent showed the enhanced absorption capacity. On the contrary, the absorption rates were $1.1610kg_{f}/cm^2{\cdot}min$ for 30 wt% MEA, $0.5310kg_{f}/cm^2{\cdot}min$ for mixture of 20 wt% thermal degraded absorbent (DP) and 10 wt% PZ and $0.3525kg_{f}/cm^2{\cdot}min$ for 30 wt% thermally degraded absorbent only. The absorption rates of PZ added thermally degraded absorbent was higher than that of thermally degraded absorbent only. Therefore, it can be confirmed that thermally degraded absorbent can be reused as an absorbent for $CO_{2}$ by the addition of suitable additives.

• Transactions of the Korean hydrogen and new energy society
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• v.28 no.5
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• pp.561-569
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• 2017

In this study, a synthetic amine made using the ethylene oxide-ammonia reaction was used as an absorbent to remove carbon dioxide. Existing absorbents were used in a mix in order to improve performance; however, because the ethylene oxide-ammonia reaction generates primary, secondary, and tertiary amines simultaneously, it has the merit that separate mixing of the absorbents was not needed. The performance of carbon dioxide absorption with the synthetic amine was compared to that of MEA. As a result of an experiment, it was determined that the $CO_2$ loading was 1.15 times better than that of MEA (a commonly used amine), while the cyclic capacity was 2.28 times higher. Because the heat of reaction was 1.10 times lower than for MEA, the synthetic amine showed superior performance in terms of absorption and regeneration.

• Journal of Environmental Science International
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• v.25 no.3
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• pp.385-393
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• 2016

Oxidative and thermal degradation of alkanolamines for a promising $CO_2$ capture technology of absorption might cause decrease in $CO_2$ capture efficiency and formation of hazardous byproducts. In this study, characteristics of a representative absorbent of monoehtanolamine (MEA) were examined for a long term operation using a laboratory scale absorption system. An $CO_2$ absorption system with ID 56 mm and absorption zone height 100 cm was developed for the characterization. Absorption solution of 30 wt% MEA was circulated at 100 mL/min to treat air with 15% $CO_2$ and 1 ppm NO at 10 L/min. Temperatures of absorber and stripper were maintained at $40^{\circ}C$ and $120^{\circ}C$, respectively. For the course of 5 weeks continuous operation, MEA concentration was decreased approximately by 70% and $CO_2$ removal efficiency was dropped from 95% to 65%. Ionic byproducts of $NH_4{^+}$, $NO_2{^-}$, and $NO_3{^-}$ were accumulated up to 48 g/mL, 0.2 g/mL, and 1.5 g/mL, respectively, tracking the variation of MEA concentration. Formation of various organic byproducts were also observed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.8
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• pp.545-552
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• 2010

Research and development efforts to reduce $CO_2$ emission are in progress to cope with global warming. $CO_2$ emission from fossil fuel fired power plants is a major greenhouse gas source and the post-combustion $CO_2$ capture is considered as a short or medium term option to reduce $CO_2$ emissions. In this study, the application of the post-combustion $CO_2$ capture system, which is based on chemical absorption and stripping processes, to typical fossil fuel fired power plants was investigated. A coal fired plant and a natural gas fired combined cycle plant were selected. Performance of the MEA-based $CO_2$ capture system combined with power plants was analyzed and overall plant performance including the energy consumption of the $CO_2$ capture process was investigated.

• Applied Chemistry for Engineering
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• v.18 no.3
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• pp.239-244
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• 2007

For the simultaneous methane recovery and $CO_2$-stripping, we have been developed dual vent auto circulation bubble lift column reactor, and evaluate optimum conditions for monoethanolamine (MEA) solutions as a $CO_2$ absorbent. At the 5 wt% MEA solution, we investigated the pH change during $CO_2$-stripping and absorption reaction, $CO_2$-stripping rate with reaction time, methane recovery efficiency for various inflow rates of air, $CO_2$-stripping rate for flow liquid over flow height, and $CO_2$-stripping dependency on the temperature of absolvent solutions. The suggested optimum conditions for $CO_2$ recovery with MEA in the dual vent auto circulation bubble lift column reactor were 40 mm over flow liquid height, 1.5 L/min of air inflow rate, and $25^{\circ}C$ of absorbent solution temperature.