• Korean Chemical Engineering Research
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• v.40 no.6
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• pp.664-668
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• 2002

In this work, the catalytic reduction mechanisms of NO over ACFs/copper prepared by electrolytic copper plating has been studied. It was found that copper content on carbon surfaces increased with increasing the plating time. However, a slightly gradual decrease of adsorption properties, such as, BET specific surface area, was observed in increasing the plating times within the range of well-developed micropore structures. As experimental results, nitric oxide was converted into the nitrogen and oxygen on ACFs and ACFs/copper catalyst surfaces at $500^{\circ}C$. Especially, the surfaces of ACFs/copper catalyst were found to scavenge the oxygen released by catalytic reduction of NO, which could be explained by the presence of another nitric oxide reduction mechanism between ACFs and ACFs/copper catalysts.

• Clean Technology
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• v.8 no.1
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• pp.53-59
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• 2002

$Cu-CeO_2$ catalysts were prepared by co-precipitation and liquid phase oxidation (CP-LPO) and the prepared catalysts were examined as selective oxidation of carbon monoxide catalysts for the application of fuel cell vehicles. The prepared $Cu-CeO_2$ catalysts showed high reaction activity, but it was hard to find the correlation between the amount of Cu loaded and the reaction activities. As increase of the amount of Cu loaded, the micro pore structure of the catalyst was changed. It is due to the formation of solid solution between Cu and $CeO_2$. During pretreatment, the catalyst formed the solid-solution of Cu-Ce-O, resulting in the improvement of catalytic activity.

• Applied Chemistry for Engineering
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• v.4 no.4
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• pp.721-730
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• 1993

Various catalysts of $Cu_xH_3-{_{2x}}PMo_{12}O_{40}{\cdot}_nH_2O$ with different x-values have been prepared and characterized by thermal analysis, X-ray powder diffraction, infrared spectroscopy, BET surface-area measurement, electron microscopy, and temperature programmed desorption of ammonia. The properties of these catalysts in acrolein oxidation have been investigated in a continuous-flow fixed-bed reactor. The catalysts lost their water of crystallization at about $200^{\circ}C$ and their constitutional water between 300 and $400^{\circ}C$. The Keggin structure of the catalysts was identified by infrared spectroscopy. The decomposition of Keggin anion, $(PMo_{12}O_{40})^{3-}$, was increased with the increase of substituted copper content and identifiable $MoO_3$ and $P_2O_5$ as decomposition products were observed. The conversion of acrolein decreased with the increase of x probably due to the decrease of specific surface area and of total amount of acid sites. But specific reaction rate and selectivity to acrylic acid were maximized at x=1.0, and it showed specific acid site distributions.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1994.11a
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• pp.97-100
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• 1994

산화구리가 담지된 알루미나 흡수제/촉매를 이용하여 유황산화물과 질소산화물의 제거반응 특성을 고정층 반응기를 이용하여 고찰하였다. 반응온도가 증가할 수록 $350^{\circ}C$까지 탈질 효율이 증가하였으며 그 이상의 온도에서는 암모니아의 산화에 의하여 탈질효율이 감소하였다. 암모니아의 $NO_{x}$ 선택성은 $SO_{x}$ 가 존재하지 않는 경우에 $NH_3/NO_{x}$mole 비 1.0 까지 유지되었으나 $SO_{x}$ 가 존재하면 선택성은 매우 감소하였다. 동시제거 반응의 경우 $400^{\circ}C$ 이상에서 효과적이었으며 $350^{\circ}C$ 이하에서는 암모늄 염의 생성으로 인하여 탈질효율의 감소가 반응시간이 증가함에 따라서 감소하였다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.154-154
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• 2016

다공성 수지상 구리분말은 그 구조적 특성으로 인해 다양한 촉매 분야에 사용되어왔으며, 본 연구에서는 전해도 금욕의 종류에 따라 수지상 구리의 표면적 특성에 대해 연구하였다. 도금욕의 종류($CuSO_4$, $CuCl_2$, $Cu_2P_2O_7$), 인가 전위, 도금시간(1, 5, 10, 30min)에 따른 수지상 형상을 비교하였다. SEM 이미지 분석 결과 황산구리와 염화구리 도금용액에서는 plate-like dendrite 형상이 관찰되었으며, 피로인산구리 도금용액에서는 needle-like dendrite 형상이 관찰되었다. 정전위 실험결과 도금용액별 한계전류밀도에서 음(-)의 방향으로 100mV 낮은 지점의 인가 전위 및 도금시간 10분에서 3가지 용액 모두 가장 미세한 수지상 입자가 관찰되었다. 도금용액별 겉보기 밀도 및 BET 비표면적을 측정해본 결과 미세한 수지상일수록 겉보기밀도는 낮게 비표면적은 크게 측정되었다. 가장 낮은 겉보기 밀도와 가장 높은 BET 비표면적을 가지는 용액은 염화구리 도금용액이었으며 그 값은 $0.951g/cm^3$, $1.8052m^2/g$이었다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2013.05a
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• pp.167-167
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• 2013

유체 플라즈마 공정(SPP)은 고에너지를 가지는 플라즈마를 유체 내에 발생시키는 공정으로서 나노유체 및 촉매 물질 제조 등 여러 가지 응용분야에 적용할 수 있다. 본 연구에서는 SPP를 이용하여 구리 나노입자를 합성하였고 방전시간과 전원공급장치의 변화에 따른 구리 나노입자의 특성과 구리 나노유체의 열전도도을 분석하였다.

• Korean Chemical Engineering Research
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• v.49 no.5
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• pp.530-534
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• 2011

The synthesis of dimethyl carbonate by liquid phase oxidative carbonylation of methanol was studied under batch reaction system. Reaction factors such as effect on various metals, anion containing in copper catalyst, temperature, carbon monoxide and oxygen molar ratio and copper content were investigated. In particular $CuCl_2{\cdot}2H_2O$ showed the excellent of the methanol conversion 65.2%, DMC selectivity 96.6% reaction condition under 1.0 g, $150^{\circ}C$, MeOH/CO/$O_2$=0.2/0.215/0.05 (molar ratio). $CuCl_2$ led to corrosion of the reactor. Thus, a new catalyst system using supports was investigated to resolve these corrosion problem. Influence on various supports were examined and copper catalyst supported on zeolite Y showed the most excellent activity on the formation of dimethyl carbonate. The amount of Fe dissolved during the reaction using ICP-AES (Inductively Coupled Plasma-Atomic Emission Spectrometer) was compared with catalysts, calcined Cu/zeolite Y showed the lower value below 5% than $CuCl_2-2H_2O$.

• Journal of the Korean Institute of Gas
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• v.27 no.1
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• pp.78-85
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• 2023

Fixed-bed reactor Computational Fluid Dynamics (CFD) simulation of methanol steam reforming reaction was performed using the intrinsic kinetic data of the copper-impregnated hydrotalcite catalyst. The activation energy of the copper hydrotalcite catalyst obtained from the previous study results was 97.4 kJ/mol, and the pre-exponential was 5.904 × 10¹⁰. Process simulation was performed using the calculated values and showed a similar tendency to the experimental results. And the conversion rate according to the change of the reaction temperature (200 - 450 ℃) and the molar ratio of methanol and water was observed using the intrinsic kinetic data. In addition, mass and heat transfer phenomena analysis of a commercial reactor (I.D. 0.05 - 0.1m, Length 1m) was predicted through axial 2D Symmetry simulation using the power law model of the above kinetic constants.

• Applied Chemistry for Engineering
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• v.25 no.5
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• pp.531-537
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• 2014

A catalytic plasma reactor was employed for the oxidation of isopropyl alcohol (IPA) classified as a volatile organic compound (VOC). Copper oxide (Cu : 0.5% (w/w)) supported on a multichannel porous ceramic consisting of ${\alpha}-Al_2O_3$ was used as a catalyst, which was directly exposed to the plasma created in it. The effects of discharge voltage and reaction temperature on the concentrations of IPA and its byproducts were examined to understand the behavior of the catalytic plasma reactor. Without thermal insulation, the reactor temperature increased up to $120^{\circ}C$ at an applied voltage of 17 kV (discharge power : 28 W), and the IPA at a flow rate of $1L\;min^{-1}$ ($O_2$ : 10% (v/v); IPA : 1000 ppm) was completely removed. At temperatures below $120^{\circ}C$, however, besides the desirable product $CO_2$, several unwanted byproducts such as acetone, formaldehyde and CO were also formed from IPA. On the other hand, when the reactor was thermally insulated, the plasma discharge increased the temperature up to $265^{\circ}C$ under the same condition and most of IPA was oxidized to $CO_2$. Without loading CuO on the ceramic support, the plasma discharge in the thermally insulated reactor produced nearly equal amounts of $CO_2$ and CO. On comparison, with the catalyst alone (temperature : $265^{\circ}C$), more than 70% of the removed IPA was simply converted into another type of VOC (acetone), indicating that the catalyst assisted by the plasma is more effective in the oxidation of IPA than that of the catalyst-alone process.

• Applied Chemistry for Engineering
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• v.20 no.4
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• pp.381-385
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• 2009

A basic objective is the preparation and surface studies of supported molten salt catalysts because molten salts can stay as the liquid phase in the range of the ordinary reaction temperature. Many kinds of metal salt mixtures for the formation of molten salt phase are appliable but CuCl and KCl were selected in this study because Cu is considered catalytically reactive in many reactons. The loading of the molten salt was selected as 25 vol% of the total pore volume of ${\gamma}-alumina$ to provide reasonable exposed surface area. The surface structure of catalysts containing molten salts in the ${\gamma}-alumina$ was studied using scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). CuCl and KCl were added into the ${\gamma}-alumina$ using concentrated hydrochloric acid solution by the impregnation technique. The surfaces of the prepared catalysts before and after heat treatments were compared and they suggested that the heat treatment of catalysts helped the formation of molten-salt although the surface compositions of CuCl and KCl were not uniform.