• 제목/요약/키워드: Cu-catalyst

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N3S-ligated Copper(II) Complex Catalyzed Selective Oxidation of Benzylic Alcohols to Aldehydes under Mild Reaction Conditions

  • Dharmalingam, Sivanesan;Koo, Eunhae;Yoon, Sungho;Park, Gyoosoon
    • Bulletin of the Korean Chemical Society
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    • 제35권3호
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    • pp.715-720
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    • 2014
  • A Cu(II) complex with an three nitrogens and one sulfur coordination environment was synthesized and characterized. Its redox potential was observed at 0.483 V vs. NHE, very similar to that of a Cu-containing fungal enzyme, galactose oxidase, which catalyzes the oxidation of alcohols to corresponding aldehydes with the concomitant reduction of molecular oxygen to water. The Cu(II) complex selectively oxidizes the benzylic alcohols using TEMPO/$O_2$ under mild reaction conditions to corresponding aldehydes without forming any over-oxidation product. Moreover, the catalyst can be recovered and reused multiple times for further oxidation reactions, thus minimizing the waste generation.

Adsorption and Thermal Reduction Mechanism of CO2 on ZnO/Cu Model Catalysts

  • Kim, Yeonwoo;Kim, Sehun
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.191.2-191.2
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    • 2014
  • Cu/ZnO/$Al_2O_3$ is widely used methanol synthesis catalyst at elevated pressures P (50 to 100 bar) and temperatures T (473 to 573 K) using $CO_2$, CO, $H_2$ syngas mixture. Although Cu step and planar defects have been regarded as active sites in this catalyst, detailed $CO_2$ hydrogenation procedure has been still unknown and debated as well as initial intermediate. In this study, we investigated the mechanism of $CO_2$ hydrogenation on Cu(111) model surface at P (1 bar) and T (298 to 450 K) using reflection absorption infrared spectroscopy (RAIRS). Two distinct formates by hydrogenation of $CO_2$, on step and on terrace, show different behavior with elevating temperature. The peak intensity of on step formate was continuously decreased above 360 K up to 450K in contrast to the increase of on terrace formate. These phenomena are strong possibilities that the formate is initial intermediate and is desorbed by hydrogenation reaction because thermal desorption temperature of formate (~470 K) is much higher than desorption of on step formate. And the formate production peak of on step site was weakly correlated with CO formation.

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플라즈마 처리와 결합된 Cu 촉매반응 화학기상증착법의 메커니즘과 고종횡비 패턴의 충진양상 전산모사에 대한 연구 (Study on the Mechanism and Modeling for Super-filling of High-Aspect-Ratio Features with Copper by Catalyst Enhanced Chemical Vapor Deposition Coupled with Plasma Treatment)

  • 김창규;이도선;이원종
    • 대한금속재료학회지
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    • 제49권4호
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    • pp.334-341
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    • 2011
  • The mechanism behind super-filling of high-aspect-ratio features with Cu by catalyst-enhanced chemical vapor deposition (CECVD) coupled with plasma treatment is described and the metrology required to predict the filling feasibility is identified and quantified. The reaction probability of a Cu precursor was determined as a function of substrate temperature. Iodine adatoms are deactivated by the bombardment of energetic particles and also by the overdeposition of sputtered Cu atoms during the plasma treatment. The degree of deactivation of adsorbed iodine was experimentally quantified. The quantified factors, reaction probability and degree of deactivation of iodine were introduced to the simulation for the prediction of the trench filling aspect by CECVD coupled with plasma treatment. Simulated results show excellent agreement with the experimental filling aspects.

메탄올 산화 카르보닐화에 의한 디메틸카보네이트 합성 (Dimethyl Carbonate Synthesis by Methanol Oxidative Carbonylation)

  • 남정광;조득희;서정권;김성보
    • Korean Chemical Engineering Research
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    • 제49권5호
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    • pp.530-534
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    • 2011
  • 회분식 고압반응기에서 메탄올 산화 카르보닐화 방법에 의한 디메틸 카보네이트 제조에 대하여 연구하였다. 다양한 금속의 영향과 구리촉매에 결합된 음이온 및 반응온도, 일산화탄소, 산소의 반응물 몰비, 구리촉매 함유량 등 여러 반응조건들을 검토하였다. 특히 $CuCl_2{\cdot}2H_2O$ 촉매가 1.0 g, $150^{\circ}C$, MeOH/CO/$O_2$=0.2/0.215/0.05(molar ratio) 반응조건에서 메탄올 전환율 65.2%, 선택도 96.6%로 좋은 활성을 보였다. $CuCl_2$는 반응기의 부식을 일으킨다. 이러한 문제점을 개선하기 위하여 DMC 제조에서 담체를 이용한 새로운 촉매시스템을 검토하였다. 여러 종류의 담체중 산성이 큰 제오라이트 Y를 담체로 사용한 경우 가장 활성이 우수하였다. ICP-AES(Inductively Coupled Plasma-Atomic Emission Spectrometer)를 이용해 반응기에 용출된 Fe 양을 비교하였을 때, 제오라이트를 담체로 사용하여 제조된 구리촉매는 $CuCl_2-2H_2O$ 촉매를 직접 사용한 경우에 비해 반응기로 용출되는 철의 양은 5% 이하이었다.

노후 특수·화물 차량 PM/NOx 저감을 위한 SDPF 촉매 및 코팅 기술 연구 (A Study on Selective Catalytic Reduction on Diesel Particulate Filter Catalyst and Coating Technology the Removal of Particulate Matters and NOx for Old Special Cargo Vehicles)

  • 정관형;서필원;오형석;김종국;강소연;강정호;김현준;신병선
    • 공업화학
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    • 제32권6호
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    • pp.695-699
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    • 2021
  • 본 연구에서는, 노후된 엔진을 사용하는 트럭 및 특수차량에서 배출되는 NOx 및 PM을 동시에 제거하기 위해 SDPF 후처리 시스템 연구를 수행하였다. 우선, SDPF의 SCR 촉매를 선정하기 위해서, V/TiO2와 Cu-zeolite 촉매의 de-NOx 성능을 비교하였으며, SCR 촉매특성분석은 BET, XRD 및 NH3-TPD를 통해 분석하였다. 촉매 활성시험 결과, Cu-zeolite 촉매가 가장 우수한 내열성을 보여주었다. 최적의 SDPF 코팅을 위해서, 목표로 설정된 입자 크기에 맞추어 슬러리를 제조하였다. SCR 코팅량에 따른 SDPF의 코팅안정성과 배압 결과, SDPF 촉매를 로딩량별로 A, B, C 샘플을 제작하여 코팅안정성과 배압 및 de-NOx 성능을 비교한 결과 B 샘플에서에서 가장 우수한 결과를 보였다. 최적 SDPF 후처리시스템에 대해 엔진동력계 시험을 실시하였으며, 시험결과 Eu-5 규제를 만족하였다.

PEMFC Operation Connected with Methanol Reformer System

  • Lee, Jung-Hyun;Park, Sang-Sun;Shul, Yong-Gun;Park, Jong-Man;Kim, Dong-Hyun;Kim, Ha-Suck;Yoo, Seung-Eul
    • Carbon letters
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    • 제9권4호
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    • pp.303-307
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    • 2008
  • The studies on integrated operation of fuel cell with fuel processor are very essential prior to its commercialization. In this study, Polymer Electrolyte Membrane Fuel Cell (PEMFC) was operated with a fuel processor, which is mainly composed of two parts, methanol steam reforming reaction and preferential oxidation (PROX). In fuel processor, ICI 33-5 (CuO 50%, ZnO 33%, $Al_2O_3$ 8%, BET surface area: $66\;m^2g^{-1}$) catalyst and CuO-$CeO_2$ catalyst were used for methanol steam reforming, preferential oxidation (PROX) respectively. PEMFC was operated by hydrogen fuel generated from fuel processor. The resulting gas from PROX reactor is used to operate PEMFC equipped with our prepared anode and cathode catalyst. PtRu/C catalyst gives more tolerance to CO.

액상 슬러리 반응기에서 합성가스로부터 DME 직접 제조 (Direct Synthesis of Dimethyl Ether From Syngas in Slurry Phase Reactor)

  • 황갑진;김정민;이상호;박주식;김영호;김종원
    • 한국수소및신에너지학회논문집
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    • 제15권2호
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    • pp.119-128
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    • 2004
  • DME(Dimethyl Ether) was directly produced from the synthesis gas using the slurry phase reactor. The catalyst for DME production prepared two types (A type; Cu:Zn:Al=57:33:10, B type; Cu:Zn:Al=40:45:15, molar ratio). It was evaluated for the effect of the reaction medium oil using the small size slurry phase reactor. DME production yield and the methanol selectivity decreased in the order: n-hexadecane oil> mineral oil> therminol oil. The long-term test of DME production was carried out using A and B type catalyst, and n-hexadecane oil and mineral oil, respectively. It was confirmed that the use of A type for the catalyst and n-hexadecane for the reaction medium oil was very useful for the viewpoint of the DME production form the synthesis gas.

폐촉매 및 재활용 중간생성물의 물리화학적 특성 평가 (Physicochemical Characteristics of Waste Catalyst and Their In-Process Products from Recycling)

  • 박준석;전병도;김정대
    • 한국환경보건학회지
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    • 제37권2호
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    • pp.150-158
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    • 2011
  • This research was conducted to estimate the physicochemical characteristics of waste catalyst and its in-process product from recycling and to suggest fundamental data for religious systems such as quality standards. Mo and V contents were increased from the waste catalyst to calcinated material and oxidized material. In the results of a heavy metals leaching test, Pb was not detected in any catalyst, calcinated and oxidized materials. Cu was not detected in the catalyst. However, it was detected in ${\leq}$1.16 mg/l for calcinated material and in 1.34~13.73 mg/l for $MoO_3$ oxidezed material. Concentrations in recycling in-process products (calcinated and oxidized materials) were higher than those of waste catalyst. Oil content of catalyst waste ranged from 0.01-14.03 wt%. Oil contents of calcinated and oxidized materials were greatly decreased compared to the catalyst waste. Carbon and sulfur contents as chemical poisoning material of catalyst waste ranged from 0.33-76.08 wt% and 5.00-22.00 wt%, respectively. The carbon contents of calcinated and oxidized materials showed below 20 wt%. The sulfur content showed below 8wt% for calcinated material and below 0.22 wt% for oxidized material.