• Environmental Engineering Research
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• 제18권3호
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• pp.145-150
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• 2013

Optimal preparation guidelines of a cathode catalyst layer by non-precious metal catalysts were evaluated based on electrochemical performance in single-chamber microbial fuel cells (MFCs). Experiments for catalyst loading rate revealed that iron(II) phthalocyanine (FePc) can be a promising alternative, comparable to platinum (Pt) and cobalt tetramethoxyphenylporphyrin (CoTMPP), including effects of substrate concentration. Results showed that using an optimal FePc loading of $1mg/cm^2$ was equivalent to a Pt loading of $0.35mg/cm^2$ on the basis of maximum power density. Given higher loading rates or substrate concentrations, FePc proved to be a better alternative for Pt than CoTMPP. Under the optimal loading rate, it was further revealed that 40 wt% of FePc to carbon support allowed for the best power generation. These results suggest that proper control of the non-precious metal catalyst layer and substrate concentration are highly interrelated, and reveal how those combinations promote the economic power generation of single-chamber MFCs.

• Korean Chemical Engineering Research
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• 제46권5호
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• pp.845-851
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• 2008

티타늄이 그라프팅(grafting)된 SBA-15 촉매(Ti-grafted SBA-15)상에서 TBHP(tert-butylhydroperoxide)를 산화제로 사용하여 회분식 반응기에서 모델 황화합물 및 실제 디젤 유분(LCO; Light Cylcle Oil)의 선택산화탈황(ODS; Oxidative Desulfurization) 반응을 수행하였으며, 티타늄 함량, 산화제/황의 몰비, 반응온도의 효과 및 반응속도상수와 활성화 에너지를 조사하였다. 티타늄이 5 wt% 도입된 Ti-grafted SBA-15 촉매는 난분해성 황화합물인 디벤조티오펜(DBT; Dibenzothiophene)과 4, 6-디메틸디벤조티오펜(4, 6-Dimethyldibenzothiophene)의 설폰(sulfone) 화합물로의 산화반응 시 표준반응조건(TBHP/S=2.5, $80^{\circ}C$, 1 atm)에서 반응개시 후 20분 뒤 100% 전환되는 우수한 활성을 나타내었다. 실제 디젤유분인 LCO를 원료로 성능 시험을 한 결과 활성이 우수하게 나타났으며 Ti-grafted SBA-15 촉매는 LCO에 함유 되어 있는 난분해성 황화합물의 선택적 산화탈황촉매로써 응용 가능성을 보였다.

• 한국기계기술학회지
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• 제13권2호
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• pp.123-128
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• 2011

It has been stand high in estimation to converse from Carbon dioxide to Dimethyl Ether in new alternative fuel energy division in 21C, especially Using of DME in point of view of transportation fuel has been discussed of a new clean energy which is very lower of exhaust gas than gasoline and diesel energy. In this paper it is used ZSM-5 and I developed new catalyst by addition of cerium to control acidity. The new catalyst was proved high conversion rate, when it was conversed from methanol to DME, there wasn't any additional material except DME and water, and I overlooked reaction temperature, reaction time, amount of catalyst, amount of added cerium, effect of water content in methanol, reaction temperature by making change of reaction time. I have conclude that conversion rate to DME was increased as increased of catalyst amounts. The best catalyst condition of without additional product was treated poisoning from ZSM-5 to 5% cerium and new catalyst was not effected in purity of fuel methanol.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2014년도 추계학술대회 논문집
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• pp.127-128
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• 2014

현재 기술 산업에서 PET위 무전해 도금을 실행하기 위해 다양한 전처리 공정과 Catalyst가 소개되고 있다. 그 중에서 가장 일반적으로 사용되고 있는 Catalyst는 Palladium으로서 Tin과 산화 환원 반응으로 Electroless Copper Deposition 단계에서 구리 도금의 Target으로 작용하고 있다. 하지만 상대적으로 Palladium은 생산 비용이 높으며 Tin은 쉽게 산화되는 문제점이 남아 있다. 이를 대체하기 위한 대안 공정으로서 Palladium 대신 Silver를 이용하여 Catalyst로서의 역할을 하는 공정이다. 이전에 PET위 전처리 공정으로 Ultra Violet을 사용하여 표면을 개질 시키는 방법을 연구했으며, 그 후 Potassium Permanganate와 Silver Catalyst의 Mechanism을 연구 했다. PET 표면 개질을 거치면서 화학 구조가 바뀌어 표면에 Carbon Carbon Double Bond를 형성한다. 이때 Permanganate ion이 새로이 형성된 이중 결합과 반응하여 두 개의 extra-OH functional group을 생성함과 동시에 $MnO_2$를 만들어 표면에 흡착 시킨다. $MnO_2$는 전위차에 의해 Silver Ion과 Redox Reaction을 일으키며 실질적인 Catalyst 역할을 하게 된다. Silver Catalyst는 무전해 구리 도금 용액 안에서 Copper의 Target으로 작용한다.

• 한국대기환경학회지
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• 제21권6호
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• pp.625-630
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• 2005

This study was focused on the catalytic activity for the combustion of low-concentration methane using various commerical catalysts (six transition metal catalysts in Russia and one rare earth metal (Honeycomb) catalyst in Korea). Catalytic activity was strongly influenced by the type and loading content of metal supported in catalyst. Catalytic performance showed the highest activity in Honeycomb catalyst including rare earth metal, which was the most expensive catalyst, while the next was the catalyst supported Cu with high content (AOK-78-52) and also that supported Cr and Co (AOK-78-56). However, both AOK-78-52 and AOK-78-56 catalysts that were very cheap had lower activation energy than Honeycomb catalyst. In the economical field, both AOK-78-52 and AOK-78-56 catalysts with transition metals showed a good alternative catalyst on the combustion of methane.

• Journal of Industrial and Engineering Chemistry
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• 제68권
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• pp.364-371
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• 2018

Enzyme polymerization is a benign process exploiting the unique activity of enzymes. In this study, a peroxidase-mimetic catalyst is demonstrated as an alternative to horseradish peroxidase (HRP) for the polymerization of aniline. The mimetic catalyst successfully catalyzes the polymerization of aniline monomers to produce polyaniline (PANI) in an aqueous solution. The PANI produced is rich of para-structure that is generally observed when HRP is used as a catalyst. Compared to HRP, the peroxidase-mimetic catalyst shows a considerably higher catalytic activity at neutral and weak basic conditions (pH >6.5) and at temperatures over $45^{\circ}C$, at which HRP is denatured.

• International Journal of Automotive Technology
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• 제7권6호
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• pp.653-658
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• 2006

The enormous increase in the use of fossil energy sources throughout the world has caused severe air pollution and a depletion of energy. Besides, it seems very difficult to comply with the upcoming stringent emission standards in vehicles. In order to develop low emission engines, research on better qualified fuels as alternative fuels to secure high engine performance becomes a more important issue than ever. Since sulfur contained in diesel fuel is transformed in sulfate-laden particulate matters when a catalyst is applied, it is necessary to provide low sulfur fuels before any Pt-based oxidation catalysts are applied. But the excessive reduction of sulfur levels may cause the lubricity of fuel and engine performance to degrade. In this aspect, biodiesel fuel derived from rice bran is applied to compensate viscosity lost in the desulfurization treatment. This research is focused on the performance of an 11,000cc diesel engine and the emission characteristics by the introduction of ULSD(Ultra Low Sulfur Diesel), BD20(Diesel 80%+Biodiesel 20%) and a diesel oxidation catalyst, where BD20 is used to improve the lubricity of fuel in fuel injection systems as fuel additives or alternative fuels.

• 한국분무공학회지
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• 제18권4호
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• pp.196-201
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• 2013

SCR(Selective Catalytic Reduction) is a major after-treatment solution to reduce NOx emission in recent diesel engines. In this study, a metal foam is applied as an alternative SCR substrate and tested in a commercial diesel engine to compared with a conventional ceramic SCR system. Basic engine test from ND-13 mode shows that a metal foam catalyst has lower NOx conversion efficiency than a ceramic catalyst especially over $350^{\circ}C$. A metal foam catalyst has characteristics of high exhaust gas pressure before a SCR catalyst and high heat transfer rate due to its material and structure. NOx conversion efficiency of a metal foam catalyst shows an increasing tendency along with the increase of exhaust gas temperature by $500^{\circ}C$. The effect of urea injection quantity variation is also remarkable only at high exhaust gas temperature.

• 한국자동차공학회논문집
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• 제4권4호
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• pp.140-146
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• 1996

A large portion(above 70%) fo the hydrocorbon and NOx emissions for a typical vehicle occur mainly before the conventional underbody catalyst reaches activation temperature. To meet the stringent regulation as EC stage 2, the emissions produced during this period must be reduced. One of alternative techniques is to place CCC(Close-Coupled Catalyst) near the exhaust manifold. In this study, the characteristics of CCC are observed through EEC mode.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 추계학술대회
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• pp.451-454
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• 2006

WGS reaction over Mo2C and ceria based catalysts was investigated to develop an alternative commercial Cu-Zn/Al2O3 catalyst for fuel processor and hydrogen station. The Mo2C catalysts were prepared by a temperature programmed method and the various metal supported cerium oxide catalysts were prepared by an Impregnation method. The catalysts were characterized by the N2 physisorption, Co chemisorption, XRD, TEM and TPR. It was found that Mo2C and 0.2wt% Pt-40wt%, Ni/CeO2 catalysts had higher activity and stability than the Cu-Zn/Al203 above $260^{\circ}C$. Moreover, CO conversion of more than 85% was observed at $280{\sim}300^{\circ}C$. But all catalysts were deactivated during the thermal cycling runs. The results suggest that these catalysts are an attractive candidate for the alternative Cu-Zn/Al2O3 catalyst for fuel processor and hydrogen station applications.