• Clean Technology
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• v.19 no.3
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• pp.287-294
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• 2013

The $NH_3$-selective catalytic reduction (SCR) reaction of NO with excess of oxygen were systematically investigated over Cu-zeolite and Fe-zeolite catalysts. Cu-zeolite and Fe-zeolite catatysts to adapt the SCR technology for mobile diesel engines were prepared by liquid ion exchange and incipient wetness impregnation of $NH_4$-BEA and $NH_4$-ZSM-5 zeolites. The catalysts were characterized by BET, XRD, FE-TEM (field emission transmission electron microscopy) and SEM/EDS. The SCR examinations performed under stationary conditions showed that the Cu-exchanged BEA catalyst revealed pronounced performance at low temperatures of $200{\sim}250^{\circ}C$. With respect to the Fe-zeolite catalyst, the Cu-zeolite catalyst showed a higher activity in the SCR reaction at low temperatures below $250^{\circ}C$. BEA zeolite based catalyst exhibited good activity in comparison with ZSM-5 zeolite based catalyst at low temperatures below $250^{\circ}C$.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2004.05a
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• pp.59-65
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• 2004

동제련 공정중 Smelting에서 SiO2가 없으면 산화에 의한 생성물은 Molten Cu-Fe-O 'Oxysulphide' 와 Solid Magnetite가 된다. 이 생성물은 Cu-rich Liquid와 Cu-dilute Liquid로 분리가 불가능하다. Smelting의 목적이 Cu가 높은 Matte와 산화된 불순물의 효과적인 분리에 있으므로 이와 같은 분리가 불가능한 혼합상태를 분리해 주어야 한다. 이때 SiO2가 첨가되면 Cu-rich 상인 Matte가 FeO-rich상인 Slag로의 분리가 가능해진다. 이러한 의미에서 동제련에 있어서 규사의 성분은 매우 중요하며 현재 재생사를 규사로 대체 사용하고 있다. 한편 실리콘 모노머 합성 공정인 금속 규소와 접촉 물질(Contact Mass, 구리촉매와 조촉매)을 반응시켜 (Si+CH3Cl ${\rightarrow}$ (CH3)2SiCl3) 실리콘 모노머를 생산하는 공정중 반응이 끝난 접촉물질인 구리 폐촉매가 발생되는데 주요성분이 Cu 12%, Si80%로 재생사와 유사하여 동제련에 투입 가능 여부를 판단하기 위하여 각 공정에서의 용융실험을 통하여 결론을 도출하였고, 실 조업 Test를 거쳐 처리하게 되므로 구리 회수 및 폐기물로써의 매립을 중지 할 수 있었다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2013.05a
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• pp.133-134
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• 2013

본 연구는 비전도성 소재 상에 무전해 동도금(Electroless Copper)시 수행되는 씨앗층이나 촉매공정 없이 직접 구리 석출물을 얻는 방법 중 하나에 관한 연구이다. 실리콘 웨이퍼상에 확산방지를 위한 Ta 금속확산방지(Metal barrier)막층 형성 후 무전해 동도금에 침지 후 최소한의 전류를 인가한 결과 균일한 구리피막을 얻을 수 있었으며, 표면 및 단면 조직 분석결과 이를 확인할 수 있었다.

• Applied Chemistry for Engineering
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• v.10 no.2
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• pp.252-258
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• 1999

Tetramethyl orthosilicate (TMOS) was obtained by the direct synthesis of methanol with metallic silicon including copper compound as a catalyst and zinc compound as a promoter. The effects of the preheating temperature and the preparation method of the contact mass on TMOS synthesis were investigated. The composition effects of the contact mass which was composed of metallic silicon with copper catalyst and various metallic halide promoters including Zn, Sn or Cd compound were studied also. The best performance on TMOS synthesis was observed on a mixed bed reactor containing metallic silicon preheated with CuCl as a catalyst and $ZnCl_2$ as a promoter. When Cu/Si = 7 wt %, Zn/Cu = 7 wt % was mixed in a slurry phase and activated into contact mass at $380^{\circ}C$, the average selectivity was 87.2% in the silicon consumption of 69.2% at $220^{\circ}C$.

• Journal of the Korean Chemical Society
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• v.32 no.1
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• pp.22-29
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• 1988

The reaction of methanol-water mixture to $CO_2$ and $H_2$ on alkaline earth metal-copper-zinc oxide has been studied in the temperature range of 150 ${\sim}\;300^{\circ}C$. Generally the addition of the alkaline earth metal to Cu/ZnO resulted in an enhancement of selectivity for $CO_2$ formation and a reduction of catalytic activity. Measurable activities were found from 150$^{\circ}C$, 200$^{\circ}C$, and 250$^{\circ}C$ on Mg/Cu/ZnO, Ca/Cu/ZnO, and Ba/Cu/ZnO respectively. However, the highest selectivity for $CO_2$ formation was observed in Ba/Cu/ZnO catalyst at 250$^{\circ}C$. The effect of alkaline earth metal or ZnO on the reactivity was investigated using temperature programmed desorption of $CO_2$ or temperature programmed reduction with $H_2$ over catalysts respectively. It was found that $CO_2$ interacts more strongly in the sequence of MgO < CaO < BaO and ZnO decereases the reduction temperature of CuO. From the results, it was suggested that ZnO activates $H_2$ in the redox process of Cu component and alkaline earth metals adsorbs $CO_2$ in the catalytic process.

• Applied Chemistry for Engineering
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• v.10 no.5
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• pp.804-807
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• 1999

New copper complexes with a ligand, L(L=N,N'-cyclohexane bis(ferrocenylmethylene)amine) which was obtained from ferrocene carboxaldehyde and 1,2-diaminocyclohexane with a mole ratio of 2:1, were prepared and characterized. Those were adapted to asymmetric catalysis. The copper(II) complexes do not work in cyclopropanation of styrene and ethyl diazoacetate but copper(I) complex catalyzes. The Cu(I)LOTf (OTf=trifluorometanesulfonate) shows a good regioselectivity giving high trans to cis ratio of up to 80:20.

• Applied Chemistry for Engineering
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• v.23 no.3
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• pp.348-351
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• 2012

The effect of the addition of Cu on the catalytic activity of the $Mn/CeO_2-ZrO_2$ catalyst for the low-temperature SCR reaction of NO was investigated. Three different amounts of Cu, 5, 10, and 15 wt%, were impregnated on the $Mn/CeO_2-ZrO_2$ catalyst. The characteristics of the synthesized catalysts were examined by BET, XRD, XPS, and $H_2-TPR$ analyses. The de-NOx efficiency of the Cu-added catalysts increased with the amount of Cu. When 15 wt% Cu was impregnated, the deNOx efficiency was the highest, reaching as high as 99%. The increased deNOx efficiency is attributed to the enhanced reducing power stemming from the interaction between Mn and Cu on the catalyst surface.

• Journal of Environmental Science International
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• v.5 no.5
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• pp.579-583
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• 1996

This study is involved to develop new catalysts to decompose plastics, detergents and surfactants containing synthetic peptide bonds. As the first year research, the catalytic-hydrolysis of amide bond in copper complex was accomplished. The hydrolysis reaction in aqueous solution was monitored by UV/VIS spectroscopy. As the pH of the solution Is increased and the temperature is raised, the reaction rate increases. The reaction rate is observed as the first order kinetic behavior for the copper complex. The metal catalyzed hydrolysis mechanism is proposed cia metal-hydroxide in the pH region of 5.5 to 6.3. The results of characterization of the catalytic reaction mechanism can be applied to develop new catalysts for peptide bond degradation in further research.

• Journal of the Korean Institute of Gas
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• v.26 no.2
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• pp.14-20
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• 2022

In this study, the catalytic reaction characteristics for producing hydrogen using methanol steam reforming were investigated. Nickel and copper are frequently used in steam reforming reaction and methanol synthesis, were used as main active metals. As a support, hydrotalcite has a high specific surface area, excellent porosity and thermal stability, and has weak Lewis acid sites and basic properties. Hydrotalcite was used to identify catalysts of methanol steam reforming with catalytic activity and their properties. In this research, high reactivity was shown in the catalyst of copper metal with high reducibility. And increasing of active metal loading showed the higher the methanol conversion and hydrogen selectivity.

• Clean Technology
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• v.21 no.3
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• pp.200-206
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• 2015

In order to investigate the effect of cerium oxide addition, Cu-ZnO-CeO₂ catalysts were prepared using co-precipitation method for water gas shift (WGS) reaction. A series of Cu-ZnO-CeO₂ catalyst with fixed Cu Content (50 wt%, calculated as CuO) and a given ceria content (e.g., 0, 5, 10, 20, 30, 40 wt%, calculated as CeO₂) were tested for catalytic activity at a GHSV of 95,541 h^-1, and a temperature range of 200 to 400 ℃. Cu-ZnO-CeO₂ catalysts were characterized by using BET, SEM, XRD, H₂-TPR, and XPS analysis. Varying composition of Cu-ZnO-CeO₂ catlysts led the difference characteristics such as Cu dispersion, and binding energy. The optimum 10 wt% doping of cerium facilitated catalyst reduction at lower temperature and improved the catalyst performance greatly in terms of CO conversion. Cerium oxide added catalyst showed enhanced activities at higher temperature when it compared with the catalyst without cerium oxide. Consequently, ceria addition of optimal composition leads to enhanced catalytic activity which is attributed to enhanced Cu dispersion, lower binding energy, and hindered Cu metal agglomeration.