• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.757-763
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• 2017

The combustion test of LMP-103S, a propellant based on ADN(Ammonium Dinitramide), was performed with a 50 mN scale micro-thruster. The micro-thruster was made with photosensitive glass using MEMS manufacturing process. $Pt/{\gamma}-Al_2O_3$ was used as a catalyst to decompose LMP-103S. After injecting 90 wt.% hydrogen peroxide into combustion chamber to preheat the catalyst, LMP-103S was injected for the combustion test. As a result, the ignition and combustion of LMP-103S was confirmed in platinum catalyst environment with the combustion chamber temperature going up to $650^{\circ}C$.

• Clean Technology
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• v.15 no.1
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• pp.9-15
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• 2009

Catalytic hydrodechlorination of PCBs (polychlorinated biphenyls) included in the transformer oil was carried out to detoxify PCBs and to recycle the treated oil. Catalysts such as 0.98 wt% Pt and 0.79 wt% Pd on ${\gamma}$-alumina (${\gamma}-Al_2O_3$) support, 12.8 wt% Ni on ${\gamma}-Al_2O_3$, and 57.6 wt% Ni on silica-alumina ($SiO_2-Al_2O_3$) support were used for the catalytic hydrodechlorination. Various supercritical fluids such as carbon dioxide, propane and isobutane were used as reaction media. The effects of reaction temperature, reaction time, catalysts, and supercritical fluids on the catalytic hydrodechlorination were examined in detail. The detoxification degree increased in the order of Ni > Pd > Pt. This is possibly due to higher metal loading and larger metal size of the Ni catalyst. Below $175^{\circ}C,\;scCO_2$ was found as the most effective reaction media for the catalytic hydrodechlorination of PCBs included in the transformer oil.

• Journal of Korean Society for Atmospheric Environment
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• v.10 no.4
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• pp.281-288
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• 1994

The hydrodesulfurization (DBT) were Peformed over NiPtMo catalysts supported on HZSM-5, LaY and ${\gamma}$- $Al_2$O$_3$under high H$_2$ pressure. And the acidities of these catalysts were characterized by using TGA and DSC. The result showed that the order of the acid strength for prepared supports was HZSM -5＞LaY＞${\gamma}$- A1$_2$O$_3$. For the acid amount we obtained the same result for the acid strength The acid strength and the acid amount mainly depended on the kinds of supports whose acid site were strong or not The activity of the hydrodesulfurization decreased for catalysts which had strong acid sites. The origin of acid site was Bronsted in NH50 and NY catalysts And it was Lewis in NA catalyst The order of desorption activation energy for Pyridine was NH50＞NY>NA. And the result was the same for thiophene. The activity of the hydrodesulfurization decreased for catalysts which had strong acid sites. The conversion of DBT over NA catalyst was higher than NH and NY catalysts.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.2
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• pp.157-165
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• 2003

A combined process of non-thermal plasma and catalytic technique has been investigated to treat $CH_3$CN gas in the atmosphere. A planar type dielectric barrier discharge (DBD) reactor has been used to generate the non-thermal plasma that produces various chemically active species, such as O, N, OH, $O_3$, ion, electrons, etc. Several different types of the beads. which are Molecular Sieve (MS) 5A, MS 13X, Pt/alumina beads, are packed into the DBD reactor, and have been tested to characterize the effects of adsorption and catalytic process on treating the $CH_3$CN gas in the DBD reactor. The test results showed that the operating power consumption and the amounts of the by-products of the non-thermal plasma process can be reduced by the assistance of the adsorption and catalytic process.

• Proceedings of the KAIS Fall Conference
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• 2006.05a
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• pp.565-568
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• 2006

Fe, Co, Zn, Cu, Pt 등의 전이금속과 ZSM-5 2종($SiO_2/Al_2O_3$ 몰비: 23, 50)과 ${\gamma}-alumina$를 담체로 사용하여 촉매를 합성하였다. 합성방법은 CVD(화학기상증착법) 과 Dry Impregnation (건식함침법), Incipient Wetness Impregnation방법이 있다. CVD 방법으로 얻은 Fe/ZSM-5과 Dry Impregnation방법으로 얻은 Cu/ZSM-5은 NO저감효율에 있어 거의 비슷하였다. 지지체로 사용된 ZSM-5의 $SiO_2/Al_2O_3$의 몰 비가 작을수록, 즉 산점의 수가 많을수록 우수한 것으로 보인다.

• Applied Chemistry for Engineering
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• v.9 no.5
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• pp.624-628
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• 1998

The aromatic organic solvents(BTX) were decomposed in the fixed bed reactor packed with a 0.5% $Pt/{\gamma}-Al_2O_3$ catalyst, then, supercritical carbon dioxide(SC-$CO_2$) was used as the reaction media. And the conversion was dependent on the inlet concentration of BTX and the molar density of SC-$CO_2$. The conversion of BTX was decreased with increasing of inlet concentration, and was increased with temperature and pressure. The maximum conversion of benzene was 98.5% at $300^{\circ}C$ and 204.1 atm, and that of toluene and xylene were 82.0 and 76.5%, respectively, at $350^{\circ}C$ and 204.1 atm. The intermediate products of partial oxidation were identified as benzaldehyde, phenol, benzenemethanol, and so on. The BTX can be effectively converted into harmless $CO_2$ and $H_2O$ at appropriate operating condition. Thus, the nontoxic recovery process was suggested as the removal method of BTX.

• Bulletin of the Korean Chemical Society
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• v.19 no.7
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• pp.733-737
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• 1998

Using an atom superposition and electron delocalization molecular orbital (ASED-MO) method, we have compared adsorption properties of adsorbates on the Pt(Ill) surface with the Pt(lll)/γ-Al203 surface in the ethylene hydrogenation reaction. In two-layer thick model systems, the calculated activation energy of the hydrogenation by the surface platinum hydride is equal to the energy by the hydride over supported platinum/γ-alumina. The transition structure on platinum is very close to the structure on the supported platinum/γ-alumina surface. Hydrogenation by the surface hydride on platinum can take place easily because the activation energy is about 0.5 eV less than hydrogenation by ethylidene. On supported platinum/,y-alumina the activation energy of the hydride mechanism is about 0.61 eV less than that of ethylidene mechanism. In one-layer thick model systems, the activation energy of hydrogenation by ethylidene is about 0.13 eV less than the activation energy of hydride reaction. The calculated activation energy by the hydride over the supported platinum y-alumina is 0. 24 eV higher than the platinum surface. We have found from this result that the catalytic properties of one-layer thick model systems have been influenced by the support but the two-layer thick model systems have not been influenced by the support.

• Journal of environmental and Sanitary engineering
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• v.15 no.3
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• pp.88-93
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• 2000

The objective of this study was to depict the kinetic behavior of the platinum catalyst for the deep oxidation of VOCs and their mixture. The oxidation characteristics of VOCs, which were benzene, toluene, and styrene, was studies on a 0.5% $Pt/{\gamma}-Al_2O_3$ catalyst. The reactivity increases in order benzene>toluene>styrene. In mixtures, remarkable effects on reaction rate and selectivity have been evident ; the strongest inhibiting effect was shown by styrene and increases in a reverse order with respect to that of reactivity. The reaction model reveals that there is a competition between the two reactants for the oxidized catalyst. Thus, the nontoxic catalytic oxidation process was suggested as the new VOCs control technology.

• Proceedings of the KAIS Fall Conference
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• 2006.05a
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• pp.561-564
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• 2006

Fe, Co, Zn, Cu, Pt 등의 전이금속과 ZSM-5 2종($SiO_2/Al_2O_3$ 몰비: 23, 50)과 ${\gamma}-alumina$를 담체로 사용하여 촉매를 합성하였다. 합성방법은 CVD(화학기상증착법) 과 Dry Impregnation (건식함침법)방법이었다. CVD 방법으로 얻은 Fe/ZSM-5는 지지체로 사용된 ZSM-5의 $SiO_2/Al_2O_3$의 몰 비가 작을수록, 즉 산점의 수가 많을수록 Fe 담지 량이 증가하는 것으로 보인다. 등온 환원 온도 $400^{\circ}C$에서 수소 환원 양이 최대로 나타나며, 이는 보고되는 $400^{\circ}C$에서의 최대 NOx 제거 반응 속도와 비례하는 것으로 나타난다.

• Journal of environmental and Sanitary engineering
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• v.16 no.3
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• pp.72-79
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• 2001

The selective catalytic oxidation of toxic aromatic solvents (benzene, toluene, ethylbenzene, and styrene) and their mixtures were studied on a $Pt/{\;}{\gamma}-Al_2O_3$ catalyst at temperature ranging from $160~350^{\circ}C$. The deep conversion of aromatic solvents was increased as the inlet concentration was decreased and the reaction temperature was increased. The reactivity increases in order benzene > toluene > ethylbenzene > styrene. In mixture, remarkable effects on reaction rate and selectivity have been evidence ; the strongest inhibition effect is shown by styrene and increase in a reverse order with respect to that of reactivity. The inhibition effect was increased in order styrene > ethylbenzene > toluzene > benzene. This trend is due to the competition adsorption between the two or three reactants on the oxidized catalyst. Also, the deep conversion change of benzene was a small in tertiary mixtures(including of benzene and styrene) comparing with conversion characteristics of binary mixture with styrene. This result was due to small concentration of styrene. which had very strong inhibition effect.