• 제목/요약/키워드: Catalyst:

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저온플라즈마와 촉매를 이용한 톨루엔 분해 연구 (Study of toluene decomposition using nonthermal plasma and catalyst)

  • 임윤희;이주열;신재란;최진식;박병현
    • 한국응용과학기술학회지
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    • 제31권4호
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    • pp.541-548
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    • 2014
  • This study was performed to obtain high conversion efficiency of $C_7H_8$ using non-thermal plasma and metal-supported catalyst. Adsorption-desorption characteristics of toluene was performed using 4A type (Zeolite) filled in a concentration reactor. Through this test, it was found that the concentration reactor has 0.020 g/g of adsorption capacity (at ambient temperature and pressure) and 3,600 ppm of desorption property at $150^{\circ}C$ (with in 20 min). In case of developed catalyst, toluene decomposition rate of Pd-AO (Pd coated catalyst) was better than Pd/Cu-AO and Pd/Ag-AO (Pd/Ag composite metal catalyst). Developed non-thermal plasma system was obtained flame amplification effect using injection process of desorbed tolune, and 98% of removal efficiency.

산화구리 촉매담지 세라믹 캔들필터를 이용한 NO 제거 (Removal of NO Using CuO/3Al2O3 · 2SiO2 Catalyst Impregnated Ceramic Candle Filters)

  • 홍민선;문수호;이재춘;이동섭
    • 한국대기환경학회지
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    • 제20권3호
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    • pp.291-302
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    • 2004
  • The CuO/$3AL_2O_3{\cdot}2SiO_2$ catalyst impregnated ceramic candle filters for nitrogen oxides removal were prepared by porous mullite($3AL_2O_3{\cdot}2SiO_2$) support and CuO catalyst deposited on this support to achieve uniformly dispersed CuO deposition, which are impregnated into the pores of available alumino-silicate ceramic candle filter. The CuO/3$AL_2O_3{\cdot}2SiO_2$ catalyst impregnated ceramic candle filters were characterized by XRD, BET, air permeability, pore size, SEM and catalytic tests in the reduction of NOx by NH$_3$. The observed effects of CuO/3$AL_2O_3{\cdot}2SiO_2$ impregnated ceramic candle filters in SCR reaction are as follows : (1) when the content of CuO catalyst increased further, activity of NO increased. (2) NO conversion at first increased with temperature and then decreased at high temperatures (above 40$0^{\circ}C$), possibly due to the occurrence of the ammonia oxidation reaction. (3) In pilot plant test for 3 months, NO conversion was greater than 90%.

초소형 연소기를 위한 촉매 합성, 담지방법 및 담지체 (Catalyst Preparations, Coating Methods, and Supports for Micro Combustor)

  • 진정근;김충기;이성호;권세진
    • 한국연소학회지
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    • 제11권2호
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    • pp.7-14
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    • 2006
  • Catalytic combustion is one of the suitable methods for micro power source due to high energy density and it can be applied to micro structured chamber without consideration of quenching since it is flameless combustion. Catalyst loading in the micro structured combustion chamber is one of the most important issues in the development of micro catalytic combustors. In this research, to coat catalyst on the chamber wall, two methods were investigated. First, $Al_2O_3$ was selected as a support of Pt and $Pt/Al_2O_3$ was synthesized through the alumina sol-gel procedure. To improve the coating thickness and adhesion between catalyst and substrate, heat resistant and water solvable organic-inorganic hybrid binder was used. Porous silicon was also investigated as a catalyst support for platinum. Through the parametric studies of current density and etching time, fabrication process of $1{\sim}2{\mu}m$ of diameter and about $25{\mu}m$ depth pores was confirmed. Coated substrates were test in the micro channel combustor which was fabricated by the wet etching and machining of SUS 304. Using $Pt/Al_2O_3$ coated substrate and Pt coated porous silicon substrate, conversion rate of fuel was over 95 % for $H_2/Air$ premixed gas.

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KF/MgO 촉매를 이용한 대두유의 전이에스테르화 반응 (Transesterification Reaction of Soybean Oil over KF/MgO Catalyst)

  • 조용범;전종기;박성훈;박영권
    • 공업화학
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    • 제23권3호
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    • pp.344-347
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    • 2012
  • 본 연구에서는 기존 MgO의 염기세기를 증가시켜 전이에스테르화 반응에 있어 보다 좋은 활성을 가지는 촉매를 만들고자 하였다. MgO를 실험실에서 제조한 후 지지체로 사용하였으며 염기세기를 증가시키기 위하여 KF를 함침법으로 담지하였다. BET, XRD, XRF, $CO_2$ TPO로 촉매의 특성분석을 하였고, 대두유과 메탄올을 사용하여 바이오디젤을 합성한 후 지방산메틸에스테르 함유량을 측정함으로써 촉매의 활성을 알아보았다. 결과적으로, KF를 30% 담지한 촉매가 활성이 가장 좋은 것으로 나타났다. 이는 전이에스테르화 반응에서 중간세기 염기도가 더 많이 관여하기 때문으로 보인다.

탄소계 복합담지체에 담지된 고내구성 고분자전해질 연료전지용 백금촉매 (Highly Durable Pt catalyst Supported on the Hybrid Carbon Materials for Polymer Electrolyte Membrane Fuel Cell)

  • 박향진;허승현
    • 전기화학회지
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    • 제17권3호
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    • pp.201-208
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    • 2014
  • 본 연구에서는 산화그래핀과 카본블랙의 혼합담체를 이용하여 내구성이 향상된 백금촉매를 폴리올법으로 제조하였다. 삼전극 순환전압전류법을 이용한 전기화학성능 측정결과 적절한 비율로 조절된 혼합담지체에 백금을 담지시켰을 경우 초기 성능 감소없이 장기내구성이 향상되는 것으로 나타났다. 또한 회전원판전극을 이용하여 산소환원반응을 수행한 결과 혼합담체에 담지된 백금촉매가 카본블랙 단일담체에 담지된 백금촉매보다 우수한 고유활성값을 나타내었다.

Characteristics of the Catalysts Using Activated Carbon Nanofibers with KOH as the Support of Anode Catalyst for Direct Methanol Fuel Cell

  • Jung, Min-Kyung;Kim, Sang-Kyung;Jung, Doo-Hwan;Peck, Dong-Hyun;Shin, Jung-Hee;Shul, Yong-Gun;Yoon, Seong-Ho
    • Carbon letters
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    • 제8권1호
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    • pp.37-42
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    • 2007
  • Carbon nanofiber (CNF) grown catalytically was chemically activated with KOH to attain structural change of CNF. The structural changes of CNF through KOH activation were investigated by using BET and SEM. From the results of BET, it was found that KOH activation was effective to develop particular sizes of pores on the CNF surface, increasing the surface area of CNF. Activated CNF was applied as an anode catalyst support of fuel cell. The effects of different activation conditions including the activation temperature and the activation time on the specific surface area of the CNF activated with KOH were investigated to obtain appropriate structure as a catalyst support. The 60 wt% Pt-Ru catalyst prepared was observed by using TEM and XRD.

The Effect of K Promoter on Ni-Co (Bimetallic) Catalyst for Dry Methane Reforming

  • Dharmasaroja, Nichthima;Phongaksorn, Monrudee;Tungkamani, Sabaithip;Ratana, Tanakorn;Sornchammi, Thana
    • International Journal of Advanced Culture Technology
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    • 제3권2호
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    • pp.110-117
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    • 2015
  • 10 wt% (Ni-Co) catalysts with different Ni and Co content : 10%Ni, 9%Ni1%Co, 7%Ni3%Co, 5%Ni5%Co, 3%Ni7%Co, and 10%Co; were prepared using sol-gel method followed by incipient wetness impregnation method. To investigate the catalytic activity including the stability, dry methane reforming were demonstrated over the pelletized catalysts at $620^{\circ}C$ under atmospheric pressure in a $CH_4:CO_2:N_2$ feedstock for 360 min. The results showed that bimetallic catalysts with the Co content equal to or greater than 3% were more stable than monometallic catalysts (10%Ni and 10%Co). The temperature programmed hydrogenation interpreted that the additional of Co into Ni catalyst improved the carbon resistance from methane cracking. Promoted this type of bimetallic catalyst using 1wt% K (trimetallic catalyst) prevented the carbon formation on the catalyst. The temperature programmed desorption of $CO_2$ indicated that this trimetallic catalyst has a greater number of strong basic sites. Moreover, the appearance of K lowered the number of weak basic sites and decreased the conversion of methane by 12 %.

Stability of ZnAl2O4 Catalyst for Reverse-Water-Gas-Shift Reaction (RWGSR)

  • Joo, Oh-Shim;Jung, Kwang-Deog
    • Bulletin of the Korean Chemical Society
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    • 제24권1호
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    • pp.86-90
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    • 2003
  • Reverse-Water-Gas-Shift reaction (RWGSR) was carried out over the ZnO, $Al_2O_3,\;and\;ZnO/Al_2O_3$ catalysts at the temperature range from 400 to 700 ℃. The ZnO showed good specific reaction activity but this catalyst was deactivated. All the catalysts except the $ZnO/Al_2O_3$ catalyst (850 ℃) showed low stability for the RWGSR and was deactivated at the reaction temperature of 600 ℃. The $ZnO/Al_2O_3$ catalyst calcined at 850 ℃ was stable during 210 hrs under the reaction conditions of 600 ℃ and 150,000 GHSV, showing CO selectivity of 100% even at the pressure of 5 atm. The high stability of the $ZnO/Al_2O_3$ catalyst (850 ℃) was attributed to the prevention of ZnO reduction by the formation of $ZnAl_2O_4$ spinel structure. The spinel structure of $ZnAl_2O_4$ phase in the $ZnO/Al_2O_3$ catalyst calcined at 850 ℃ was confirmed by XRD and electron diffraction.

$N_2O$ 추진제 분해 촉매의 고온 내열 특성 연구 (Study on the Characteristics of Thermal-resistance Catalyst for $N_2O$ Propellant Decomposition)

  • 백진오;김태규
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2010년도 제34회 춘계학술대회논문집
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    • pp.373-376
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    • 2010
  • 아산화질소를 추진제로 사용하기 위해 아산화질소의 촉매 분해 특성과 고온 하에서 내열성을 연구하였다. 기존의 Ru 촉매의 내열성을 개선하기 위해 추가적으로 $Al_2O_3$ 지지체에 Si를 담지시킨 후 Ru을 담지하였다. 관형 반응기를 이용하여 반응온도에 따른 아산화질소의 전환율을 측정하고, Si 첨가에 의한 분해특성에 대해서 연구하였다. 반응온도가 높을수록 전환율이 우수했고, Ru/$Al_2O_3$-Si 촉매가 Ru/$Al_2O_3$ 촉매보다 높은 전환율을 보였다.

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수전해용 Ir/TiO2 산소 발생 촉매의 제조 및 성능 평가 (Synthesis and Evaluation of Ir/TiO2 OER catalyst for PEM water electrolysis)

  • 송민아;정혜영;이해지;최윤기;문상봉
    • 한국수소및신에너지학회논문집
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    • 제27권5호
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    • pp.471-477
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    • 2016
  • In this research, the Ir supported $TiO_2$ (P25) catalyst was prepared by precipitation method for oxygen evolution reaction. The $Ir/TiO_2$ catalyst was synthesised by reduction reaction using reducing agent. Physiochemical characterizations of synthesized $Ir/TiO_2$ catalyst was studied by means of SEM, EDS mapping, TEM and XRD. The Electrochemical characterizations were tested by using the technique of CV and LSV by RDE and Potentiostat. Physicochemical properties were characterized with XRD where Iridium metal morphology and Ir(111) and Ir(222) peaks were founded. $Ir0.2Ru0.8O_2$ exhibited higher OER activity than $Ir0.5Ru0.5O_2$ followed by $Ir/TiO_2$ and $IrO_2$.