• 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.

• Korean Chemical Engineering Research
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• v.47 no.5
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• pp.639-645
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• 2009

In this study, alkanolamine was used to achieve high absorption rates for $CO_2$ as suggested at several literatures. The absorption rates of aqueous AMP and MEA solutions with $CO_2$, $SO_2$, $NO_2$ were measured using a stirredcell reactor. The reaction rate constants were determined from the measured absorption rates. The performances were evaluated under various operating conditions. As a result, the reactions with $SO_2$, $NO_2$ into aqueous AMP and MEA solutions were classified as an instantaneous reaction respectively. The absorption rates increased with increase of the reaction temperature and the concentration of absorbents. The simultaneous absorption rate of $CO_2/SO_2/NO_2$ into 3, 5, 10 wt.% MEA at various pressure of $CO_2/SO_2/NO_2$, was more increased 14~20% than AMP solution. We investigated the effect of $SO_2$ and $NO_2$ on the simultaneous absorption of $CO_2/SO_2/NO_2$ from a flue gas. The performances were evaluated under various operating conditions in order to investigate the absorption characteristic.

• Korean Chemical Engineering Research
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• v.43 no.1
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• pp.161-169
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• 2005

Numerical simulation and experiments were carried out on the absorption of carbon dioxide using PVDF hollow-fiber membrane contactor. Water or monoethanolamine (MEA) aqueous soluton was used as absorbents. Simulation results showed that the concentration profile of carbon dioxide was less affected by the flow rate of MEA than that of water absorbent. The absorption rate and mass transfer coefficient of carbon dioxide increased as the concentration of MEA increased. The mass transfer coefficients obtained by experiments coincided with those obtained by numerical simulation and theoretical results for $CO_2-water$ system. However, for $CO_2-MEA$ system, the mass transfer coefficients obtained by experiments were lower than those obtained by simulation, while the simulation results agreed well with theoretical results. The durability of plasma-treated hollow fiber membranes was better than that of no plasma-treated ones.

• Journal of Energy Engineering
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• v.6 no.2
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• pp.203-211
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• 1997

This study is on the separation of Global warming effect gas, CO$_2$by chemical absorption from mixture of CO$_2$-N$_2$which was modeled after flue gas of fire power plant. Investigation of optimum condition for absorbent was carried out by using sparged vessel apparatus. Through packed tower experiments, applicabilities of two absorption models were tested by comparing experimental results with theoretical values. Absorbent used in the experiments was Monoethanolamine (MEA) and gas mixture was made in the mole composition of 15% CO$_2$and 85% N$_2$. Through estimations of CO$_2$loading and CO$_2$removal efficiency, optimum concentration of absorbent was found in the range of 4-5 M. To find a rate of absorption, an enhancement factor was introduced. Values of rate of absorption were calculated by Film model and Higbie model, respectively. Higbie model showed good agreement with experimental results. Therefore, this models is considered to be applicable to the CO$_2$separation process for flue gas from fire power plant.

• Journal of the Korean Applied Science and Technology
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• v.30 no.1
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• pp.88-95
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• 2013

This study attempts to capture the low level carbon dioxide from indoor spaces using a granular activated carbon (WSC-470) which was modified with primary monoethanolamine. Adsorption capacity of the prepared adsorbents was evaluated for pure $CO_2$ flow and 3000 ppm as a function of MEA concentration and solvents such as distilled water, ethanol and methanol. The AC based adsorbents then were characterized in terms of pore structure by BET and chemical functionalities by XPS. While high concentration of MEA reduced specific surface area, porosity and micro pores, nitrogen content which can enhance the surface basicity was increased. The maximum adsorption capacity decreased comparing to the initial AC pellets, whilst the potential of selective adsorption amount at low level $CO_2$ was increased at 45% (0.73 mmol/g).

• Journal of Nutrition and Health
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• v.12 no.1
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• pp.31-41
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• 1979

Free amino acid in ethanol extracts and total amino acids in hydrolysates of eleven species of edible mushrooms were analyzed and determinated the contents five kind of new amino acid by means of amino acid autoanalyzer and gas liquid chromatography. The result obtained from this study are as follows. 1) Five kind of new amino acid turned out to be ${\alpha}$-aminobutyric acid, allo-isoleucine, ethanolamine, $\gamma$-aminobutyric acid and ornithine. 2) By means of amino acid autoanalyzer, the monoethanolamine was identified on the chromatogram ahead of alanine, ${\alpha}$-aminobutyric acid between peak of threonine and glycine, allo-isoeleucine between peak of valine and leucine, isoleucine, ${\gamma}$-aminobutyric acid followed by proline between peak of leucine, isoleucine and methionine and ornithine between peak of phenylalanine and tyrosine 3) By means of Gas liquid chromatography, the ${\alpha}$-aminobutyric acid was identified on the chromatogram between peaks of alanine and valine, allo-isoleucine between peaks of methionine and isoleucine, monoethanolamine followed by ${\gamma}$-aminobutyric acid between peaks of phenylalanine and ammonia, ornithine between the peaks of ammonia and lysine. 4) Of five amino acids which were identified, ornithine was the highest of its content in the mushroom extracts, and allo-isoleucine, ethanolamine, and ${\gamma}$-aminobutyric acid came next in decreasing order. 5) Also which were identified, ornithine was the highest of its content in the hydrolysates, and ${\alpha}$-aminobutyric acid, ${\gamma}$-aminobutyric acid, allo-isoleucine came next in decreasing order, ethanol extracts and hydrolysates of Auriculariaauricula-Judae(Fr.) $Qu\acute{e}l$ species didn't contain any of five kind of new amino acid. Ornithine also was the highest in the hydrolysates of ll mushrooms.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.15 no.3
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• pp.270-276
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• 2005

This study was conducted to examine whether a specific synthetic metalworking fluid (MWF), "A", in use for 10 months without replacement, displayed microbial resistance and to identify the additives associated with the control of microbial growth. Three synthetic MWF products ("A", "B", and "C") were studied every week for two months. Microbial deterioration of the fluids was assessed through evaluation by endotoxin, bacteria and fungi levels in the MWFs. In addition, formaldehyde, boron, ethanolamine, and copper levels were also studied to determine whether they influence microbial growth in water-based MWFs. Throughout the entire study in the sump where MWF "A" was used, bacteria counts were lower than 103 CFU/mL, and endotoxins never exceeded 103 EU/mL. These levels were significantly lower than levels observed in sumps badly deteriorated with microbes. Boron levels in MWF "A" ranged from 91.7 to 129.6 ppm, which was significantly higher than boron levels found in other MWF products. The total level of ethanolamine (EA) in MWF "A" ranged from 35,595 to 57,857 ppm (average 40,903 ppm), which was over ten times higher than that found in other MWFs. Monoethanolamine (MEA), diethanolamine (DEA) and triethanolamine (TEA) concentrations in MWF "A" were also significantly higher than seen in other MWFs. However, although EA and boron might improve anti-microbial performance, their abuse can pose a serious risk to workers who handle MWFs. From an industrial hygiene perspective, our study results stress that the positive synergistic effect of boron and EA in reducing microbial activity in MWF must be balanced with the potentially negative health effects of such additives. Our study also addresses the disadvantage of failing to comprehensively report MWF additives on Material Safety Data Sheets (MSDS). Future research in MWF formulation is needed to find the best level of EA and boron for achieving optimal synergistic anti-microbial effects while minimizing employee health hazards.

• Korean Chemical Engineering Research
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• v.40 no.6
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• pp.719-724
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• 2002

Celgard and Durapore membranes were plasma-treated to enhance the hydrophobicity and durability to amine solution. The plasma gases or vapors used were $CF_4$, Hexafluorobenzene(HFP), Pentafluoropyridine(PFP) and Hexamethyldisiloxane(HMDS). The surface structure of plasma treated membranes was analyzed by FT-IR spectra. The contact angles of plasma treated Celgard and Durapore were dependent of the plasma gases used. $CF_4$ and HMDS plasma increased the contact angles of Celgard and Durapore, while HFB and PFP plasma decreased the contact angles. Durability to monoethanolamine(MEA) solution was enhanced for $CF_4$ plasma-treated Durapore, while the durability was not good for plasma-treated Celgard.

• 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.

• Korean Chemical Engineering Research
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• v.50 no.2
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• pp.244-250
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• 2012

In order to separate of carbon dioxide in the combustion exhaust gas, monoethanolamine (MEA) and piperazine (PZ) impregnated zeolite 13X adsorbents were used. A series of adsorbents were synthesized by impregnating 30, 50 and 70 wt% of MEA and PZ respectively on zeolite 13X pellet. XRD, FT-IR and BET were used to characterize the properties of impregnated pelletized zeolite 13X absorbents. In order to investigate the separation characteristics of carbon dioxide, zeolite pellet, MEA impregnated zeolite and PZ impregnated zeolite pellet were investigated at 25, 50 and $75^{\circ}C$. Amine impregnated pelletized zeolite absorbent has shown that adsorption decreases with increasing temperature. Finally, the carbon dioxide adsorption capacity when emission temperature of the combustion exhaust gas, PZ impregnated zeolite pellet was 1.8 times than zeolite pellet as well as 20 times than MEA impregnated zeolite pellet.