• 한국산학기술학회논문지
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• 제18권9호
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• pp.473-479
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• 2017

환경오염과 인체의 유해성 및 지구온난화로 인하여 자동차의 파워트레인의 변화가 심화되고 있으며 전기자동차의 시장점유율이 상승하고 있다. 또한, 화석연료를 기반으로 하는 내연기관 자동차의 엄격한 배기가스규제를 충족시키기 위해 자동차와 선박용 후처리장치의 비중이 점차로 증가하고 있다. 이 연구의 목적은 CNG 버스에서 배출되는 유독성 가스를 저감하는 NGOC의 $CH_4$와 NOx 저감 능력 향상을 위하여 조촉매 $CeO_2$ 담지량에 영향을 파악하는 것이다. 3종의 천연가스산화촉매(NGOC)를 Fresh 조건과 $700^{\circ}C$ 12hr 열적 열화 조건으로 촉매를 제조한 후 유해가스 저감 성능을 평가하였다. $CeO_2$는 일반적으로 산화 환원반응성이 좋아 촉매활성에 좋다고 알려져 왔으며, 안정적인 물질인 $CH_4$와 NOx 저감 능력에 미치는 영향을 연구하는 것은 의의가 있다. 6wt% $CeO_2$가 담지된 Fresh $1Pt-3Pd-1Rh-3MgO-6CeO_2/(Al+Z)$ NGOC는 $CH_4$에 대한 선택도가 큰 Pd의 분산도가 제일 높았고 유해가스 저감 성능도 향상되었다. $700^{\circ}C$ 12hr 고온조건에서 내구성이 낮은 지지체 zeolite의 화합물 결정이 일부 파괴되면서 zeolite의 결정체인 $Al_2O_3$가 떨어져 나와 응집되었다. 6wt% $CeO_2$가 담지된 NGOC는 귀금속의 분산도 저하가 가장 작았고, $CeO_2$의 열적인 내구성으로 인하여 유해가스 저감 성능이 가장 높았다.

• 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.

• Journal of Mechanical Science and Technology
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• 제20권1호
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• pp.1-12
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• 2006

This work reviews the effects of catalyst formulation and exhaust gas composition on soot oxidation in CDPF (Catalytic Diesel Particulate Filter). DOC's (Diesel Oxidation Catalysts) have been loaded with Pt catalyst (Pt/$Al_{2}O_3$) for reduction of HC and CO. Recent CDPF's are coated with the Pt catalyst as well as additives like Mo, V, Ce, Co, Fe, La, Au, or Zr for the promotion of soot oxidation. Alkali (K, Na, Cs, Li) doping of metal catalyst tends to increase the activity of the catalysts in soot combustion. Effects of coexistence components are very important in the catalytic reaction of the soot. The soot oxidation rate of a few catalysts are improved by water vapor and NOx in the ambient. There are only a few reports available on the mechanism of the PM (particulate matter) oxidation on the catalysts. The mechanism of PM oxidation in the catalytic systems that meet new emission regulations of diesel engines has yet to be investigated. Future research will focus on catalysts that can not only oxidize PM at low temperature, but also reduce NOx, continuously self-cleaning diesel particulate filters, and selective catalysts for NOx reduction.

• 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.

• 한국수소및신에너지학회논문집
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• 제34권6호
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• pp.587-593
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• 2023

This research project focused on the production of hydrogen through ammonia decomposition reactions while investigating how the reactivity of this process varies when employing different catalysts. Several metal oxide supports (Al₂O₃, La₂O₃, CeO₂) were utilized as catalysts, with active metals from both the transition metal group (Co, Ni, Fe, Cr, Cu) and the noble metal group (Ru, Rh, Pd, Pt) impregnated onto these supports. Furthermore, the study examined how the reactivity evolves with changes in reaction temperature when employing the prepared catalysts. Additionally, the research delved into the distinctive activation energies associated with each of the catalysts. In this research, In the noble metal catalyst system, the order of high activity for ammonia decomposition reaction to produce hydrogen is Ru > Rh > Pt ≈ Pd. In the transition metal catalyst system, the order of high activity is Co > Ni > Fe > Cr > Cu.