• Title/Summary/Keyword: Alternative catalyst

Search Result 120, Processing Time 0.027 seconds

Optimal Metal Dose of Alternative Cathode Catalyst Considering Organic Substances in Single Chamber Microbial Fuel Cells

  • Nam, Joo-Youn;Moon, Chungman;Jeong, Emma;Lee, Won-Tae;Shin, Hang-Sik;Kim, Hyun-Woo
    • Environmental Engineering Research
    • /
    • v.18 no.3
    • /
    • pp.145-150
    • /
    • 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.

Characteristics of Oxidative Desulfurization(ODS) of Sulfur Compounds in Diesel Fuel over Ti-grafted SBA-15 Catalyst (Ti-grafted SBA-15 촉매를 이용한 경유유분 중의 황화합물의 선택산화탈황 특성)

  • Cho, Chin-Soo;Jeong, Kwang-Eun;Chae, Ho-Jeong;Kim, Chul-Ung;Jeong, Soon-Yong;Oh, Sung-Geun
    • Korean Chemical Engineering Research
    • /
    • v.46 no.5
    • /
    • pp.845-851
    • /
    • 2008
  • Oxidative desulfurizaton of model sulfur compounds and Industrial diesel fuel(LCO; Light Cycle Oil) over Ti-grafted SBA-15 catalyst was studied in a batch reactor with tert-Butyl Hydroperoxide(TBHP) as oxidant. Effects of Ti loading, TBHP/Sulfur mole ratio, reaction temperature on ODS activity and kinetic parameters were investigated. Ti-grafted SBA-15 catalyst showed higher sulfur removal activity in the oxidative desulfurization reaction of refractory sulfur compounds(DBT and 4, 6-DMDBT) and LCO, suggesting that Ti-grafted SBA-15 catalyst could be a good candidate for ODS catalyst.

A Study on DME Conversion rate using New Catalyst (신 촉매를 이용한 DME 전환율에 관한 연구)

  • Jeong, I.S.
    • Journal of the Korean Society of Mechanical Technology
    • /
    • v.13 no.2
    • /
    • pp.123-128
    • /
    • 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.

Alternative Eletroless Copper Plating Process Utilizing Silver Catalyst on Poly(Ethylene Terephthalate) (PET위 Silver Catalyst를 이용한 무전해 구리 도금 대안 공정)

  • Lee, Hong-Gi;Heo, Jin-Yeong;Im, Yeong-Saeng;Lee, Geon-Hyeong
    • Proceedings of the Korean Institute of Surface Engineering Conference
    • /
    • 2014.11a
    • /
    • pp.127-128
    • /
    • 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.

  • PDF

Catalytic Activity of Commercial Metal Catalysts on the Combustion of Low-concentration Methane (저농도 메탄 연소에서 상용 금속촉매의 활성)

  • Lee Kyong-Hwan;Park Jae-Hyun;Song Kwang-Sup
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.21 no.6
    • /
    • pp.625-630
    • /
    • 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.

Polymerization of aniline using a peroxidase-mimetic catalyst

  • Kim, Min-Chul;Lim, Youngjoon;Lee, Sang-Yup
    • Journal of Industrial and Engineering Chemistry
    • /
    • v.68
    • /
    • pp.364-371
    • /
    • 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.

COMBINED EFFECTS OF BD20, LOW SULFUR DIESEL FUEL AND DIESEL OXIDATION CATALYST IN A HD DIESEL ENGINE

  • Baik, D.S.
    • International Journal of Automotive Technology
    • /
    • v.7 no.6
    • /
    • pp.653-658
    • /
    • 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.

Characteristic Analysis of a SCR System using a Metal Foam in Diesel Engines (디젤 엔진에서 금속 폼을 적용한 SCR 촉매의 특성 분석)

  • Kim, Yongrae;Choi, Kyonam
    • Journal of ILASS-Korea
    • /
    • v.18 no.4
    • /
    • pp.196-201
    • /
    • 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.

Development of Close-Coupled Catalyst(CCC) System to Meet EC Stage 2 (Ec Stage 2를 위한 Close-Coupled Catalyst(CCC) System의 개발)

  • 김대중;손건석;이귀영;최병철;강상록
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.4 no.4
    • /
    • pp.140-146
    • /
    • 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.

  • PDF

Development of High Performance WGS Catalyst for Fuel Processor Applications (연료 개질기용 고성능 수성가스 전환반응 촉매 개발)

  • Lee, Yoon-Ju;Ryu, Jong-Woo;Kim, Dae-Hyun;Choi, Eun-Hyung;Noh, Won-Suck;Lee, Sang-Deuk;Moon, Dong-Ju
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2006.11a
    • /
    • pp.451-454
    • /
    • 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.

  • PDF