• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.05a
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• pp.247-250
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• 2009

The catalytic combustor has the advantage of stable combustion under very lean conditions with low emissions of $NO_x$, CO and unburned hydrocarbon(UHC). Notwithstanding these advantages, the commercial application of the catalytic combustion has been delayed due to the complicated reaction process. For the stable operation of catalytic combustor, study on the combustion characteristics of the catalytic combustor is needed. So, in this study, numerical study on the propane combustion characteristics of the catalytic combustor with Pd-based catalyst is performed.

• Journal of the Korean Chemical Society
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• v.24 no.3
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• pp.183-192
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• 1980

Oxidation reactions of carbon monoxide on $SnO_2$, Sb-doped $SnO_2$, and Pt catalyst were studied. The oxidation reaction was found to be first order with respect to both CO and O$_2$ on $SnO_2$ and Sb-doped $SnO_2$ catalysts, and to be of half order on Pt catalyst. A small addition of Sb to $SnO_2$ (depant composition: 0.05∼0.1 mol %) increased the rate of oxidation. On the contrary, a large addition decreased the rate. From the rate expression of oxidation on Pt catalyst, the inhibition effect of carbon monoxide on the rate of oxidation was deduced. The experimentally obtained activatio energies were 5.7 kcal for the Sb doped $SnO_2$ catalyst (dopant composion: 0.05 mole%), and 6.4 kcal for the Pt catalyst. A possible reaction mechanism was proposed from the experimentally obtained kinetic data.

• Applied Chemistry for Engineering
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• v.21 no.1
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• pp.63-70
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• 2010

Transition metal based spent catalysts (Ni-Mo and Co-Mo), which were scrapped from the petrochemical industry, were reused for the removal processes of volatile organic compounds (VOCs). Especially the optimum regeneration procedures were determined using the removal efficiency of VOCs. In this work, the spent Ni-Mo and spent Co-Mo catalysts were pretreated with different physic-chemical treatment procedure: 1) acid aqueous solution, 2) alkali solution, 3) chemical agent and 4) steam. The various characterization methods of spent and its regenerated catalysts were performed using nitrogen adsorption, X-ray diffraction (XRD) and scanning electron microscopy (SEM) equipped with an energy dispersive spectrometry (EDS). It was found that all spent catalysts were found to be potentially applicable catalysts for catalytic oxidation of benzene. The experimental results also indicated that among the employed physico-chemical pretreatment methods, the oxalic acid aqueous (0.1 N, $C_2H_2O_4$) pretreatment appeared to be the most efficient in increasing the catalytic activity, although the catalytic activity of spent Ni-Mo and spent Co-Mo catalysts in the oxidation of benzene were greatly dependent on the pretreatment conditions. The pretreated spent catalysts at optimum condition could be also applied for removing other aromatic compounds (Toluene/Xylene).

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.423-424
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• 2002

산성비의 원인이자 주요 대기오염물질로 규제되고 있는 질소산화물은 주로 이동오염원, 발전소 및 산업시설에서 배출되고 있으며 전 세계적으로 배출 기준이 점차 강화되고 있는 추세이다. 따라서 질소산화물을 효과적으로 제어하기 위한 기술도 다양하게 연구되고 있는데, 이중 플라즈마와 촉매를 동시에 이용할 경우 상승효과가 있음이 보고된 이후 복합공정에 관한 연구가 활발하게 진행되고 있다. (중략)

• Journal of the Korean Chemical Society
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• v.52 no.1
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• pp.23-29
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• 2008

Simple Keggin type tungsten and molybdenum heteropoly acids, H3PW12O40 and H3PMo12O40, were usedas water-tolerant catalysts for the oxidation of alcohols with 34% hydrogen peroxide in normal drinking water. Accordingto our findings, H3PW12O40 may be used as a simple, effective, and cheap catalyst for this type of transformation in nor-mal drinking water with excelent yields. Efects of diferent solvents at 25-80oC and changing concentration of catalystand substrate on the reaction progress were also studied.

• Journal of Energy Engineering
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• v.10 no.1
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• pp.40-48
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• 2001

디젤엔진에 적합한 환경 친화적 연료로 평가받고 있는 디메틸에테르(DME)를 기존의 메탄올 탈수화에 의한 간접법 대신 합성 가스로부터 직접 합성법으로 제조하였다. 합성가스에서 메탄올을 합성하는 경우에 비해 화학 평형 상의 이점 때문에 DME를 합성하는 것이 경제적이며 이는 실험 결과와 일치하였다. 기상 반응기에서 메탄올 탈수촉매의 부가에 의한 메탄올 환산 생산량은 메탄올 합성촉매에 의한 생산량에 비해 두 배 이상의 증가를 보인다. 메탄올 탈수촉매를 Cu로 개질한 효과는 없었으며, 메탄올 탈수촉매로서 순수 감마알루미나가 가장 우수한 반응성을 보였다. 반응 조건이 25$0^{\circ}C$, 30atm일 때 고려된 GHSV 범위에서 촉매 적정 혼합비는 7:3, 합성 가스의 조성비는 $H_2$/CO=1일 때 가장 좋은 선택도와 수율을 나타내었다.

• Applied Biological Chemistry
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• v.37 no.3
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• pp.189-193
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• 1994

The hydrolysis of fungicidal N-[1-(benzotriazol-1-yl)benzyl]aniline (BBA) molecule in the presence of cationic cetyltrimethylammonium bromide (CTABr) and anionic sodium laurylsulfate (NaLs) micellar solutions has been studied kinetically. The Micellar catalysis effect shows that the rate is slightly accelerated by the addition of the anionic NaLs at high pH and the binding constant (Ks) is $1.45{\times}10^4M^{-1}$. This result presumably is due to the electrostatic stabilization by the anionic micelle of the developing carbocation in the transition state rather than the hydrophobic character (${\pi}$: 4.93) of (BBA).

• Analytical Science and Technology
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• v.21 no.3
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• pp.167-173
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• 2008

In order to solve the reproduction problem of PCB, we carried out poly chlorinated biphenyl (PCB) removal at low temperature (< $220^{\circ}C$), which could not take place reproduction of PCB by over 90% on catalyst. We coated catalyst to commercial bag filter for simultaneous removal of PCB and particle. It was found that PCB could be not reproducible due to it's decomposition of benzene ring. The coating method of spray type was more useful than that of precipitation one. PCB removal conversion was highest on the Pt-Co catalyzed bag filter. The data of this study can be well used in order to remove PCB and particle simultaneously for incinerator process by substituting commercial bag filter to catalyzed bag filter.

• Clean Technology
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• v.16 no.1
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• pp.12-18
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• 2010

The object of the present study is to apply KF/MgO catalysts to remove sulfur dioxide from dibenzothiophene sulfone, a by-product of oxidative desulfurization. Potassium fluoride was deposited via an impregnation method on MgO. The effects KF loading and calcination on the characteristics of the KF/MgO catalysts were investigated through the BET surface area, XRF, XRD, and temperature-programmed desorption of $CO_2$. The catalytic performances of the samples were investigated during the decomposition of dibenzothiophene sulfone to biphenyl and sulfur dioxide gas. KF loaded on MgO prepared by the impregnation method showed high catalytic activities for the decomposition of dibenzothiophene sulfone. The higher activity of KF/MgO just dried at 373 K, avoiding the usual activation at high temperature, than that over the calcined catalyst is ascribed to increase of the amount of basic sites. The high basicity probably may be due to the coordinately unsaturated $F^-$. The simply dried 10 % KF/MgO catalyst, without the usual activation at high temperature, showed the optimal catalytic properties.

• Applied Chemistry for Engineering
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• v.34 no.6
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• pp.674-678
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• 2023

The effect of Pt was investigated to the catalytic methane decomposition of CH₄ to H₂ over Pt(1)-Fe(30)/MCM-41 and Fe(30)/MCM-41 using a fixed bed flow reactor under atmosphere. The Fe₂O₃ and Pt crystal phase behavior of fresh Pt(1)-Fe(30)/MCM-41 were obtained via XRD analysis. SEM, EDS analysis, and mapping were performed to show the uniformed distribution of nano particles such as Fe, Pt, Si, O on the catalyst surface. XPS results showed O^2-, O^- species and metal ions such as Pt⁰, Pt²⁺, Pt⁴⁺, Ft⁰, Fe²⁺, Fe³⁺ etc. When 1 wt% of Pt was added to Fe(30)/MCM-41, automic percentage of Fe2p increased from 13.39% to 16.14%, and Pt4f was 1.51%. The yield of hydrogen over Pt(1)-Fe(30)/MCM-41 was 3.2 times higher than Fe(30)/MCM-41. The spillover effect of H₂ from Pt to Fe increased the reduction of Fe particles and moderate interaction of Fe, Pt and MCM-41 increased the uniform dispersion of fine nanoparticles on the catalyst surface, and improved hydrogen yield.