• 한국응용과학기술학회지
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• 제21권3호
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• pp.225-230
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• 2004

Synthesis gas is a high valued compound as a basic chemicals at various chemical processes. Synthesis gas is mainly produced commercially by a steam reforming process. However, the process is highly endothermic so that the process is very energy-consuming process. Thus, this study was carried out to produce synthesis gas by the partial oxidation of methane to decrease the energy cost. The effects of reaction temperature and flow rate of reactants on the methane conversion, product selectivity, product ratio, and carbon deposition were investigated with 13wt% Ni/MgO catalyst in a fluidized bed reactor. With the fluidized bed reactor, $CH_4$ conversion was 91%, and Hz and CO selectivities were both 98% at 850$^{\circ}C$ and total flow rate of 100 mL/min. These values were higher than those of fixed bed reactor. From this result, we found that with the use of the fluidized bed reactor it was possible to avoid the disadvantage of fixed bed reactor (explosion) and increase the productivity of synthesis gas.

• 한국수소및신에너지학회논문집
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• 제17권3호
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• pp.293-300
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• 2006

KIER has been developing a Ru-based preferential oxidation catalysts and a novel fuel processing system to provide hydrogen rich gas to residential PEMFCs system. The catalytic activity of Ru-based catalysts was investigated at different Ru loading amount and different support structure. The obtained result indicated that 2 wt% loaded Ru-based catalyst supported on ${\alpha}-Al_2O_3$ showed high activity in low temperature range and suppressed the methanation reaction. The developed prototype fuel processor showed thermal efficiency of 78% as a HHV basis with methane conversion of 92%. CO concentration below 10 ppm in the produced gas is achieved with separate preferential oxidation unit under the condition of $[O_2]/[CO]=2.0$. The partial load operation have been carried out to test the performance of fuel processor from 40% to 80% load, showing stable methane conversion and CO concentration below 10 ppm. The durability test for the daily start-stop and 8 h operation procedure is under investigation and shows no deterioration of its performance after 50 start-stop cycles. In addition to the system design and development.

• Journal of Electrochemical Science and Technology
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• 제11권4호
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• pp.336-345
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• 2020

Nickel-doped lanthanum cobalt oxide (LaCo_1-xNi_xO_3-δ, LCN) was investigated as an alternative anode material for solid oxide fuel cells. To improve its catalytic activity for steam methane reforming (SMR) reaction, Ni²⁺ was substituted into Co³⁺ lattice in LaCoO₃. LCN anode, synthesized using the Pechini method, reacts with yttria-stabilized zirconia (YSZ) electrolyte at high temperatures to form an electrochemically inactive phase such as La₂Zr₂O₇. To minimize the interlayer by-products, the LCN was coated via a double-tape casting method on the Ni/YSZ anode as a catalytic functional layer. By increasing the Ni doping amount, oxygen vacancies in the LCN increased and the cell performance improved. CH₄ fuel decomposed to H₂ and CO via SMR reaction in the LCN functional layer. Hence, the LCN-coated Ni/YSZ anode exhibited better cell performance than the Ni/YSZ anode under H₂ and CH₄ fuels. LCN with 12 mol% of Ni (LCN12)-modified Ni/YSZ anode showed excellent long-term stability under H₂ and CH₄ conditions.

• 유기물자원화
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• 제14권4호
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• pp.93-103
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• 2006

바이오가스는 유기물의 혐기소화과정에서 생기는 부산물로 열에너지와 전기에너지로 사용되어왔다. 바이오디젤생산의 반응물과 연료로 사용되고 있는 메탄올의 수요는 꾸준히 증가하고 있다. 본 총설에서는 메탄올을 메탄올로 전환하는 직접부분산화법의 최근 발전 동향을 간략한 메탄올합성의 역사와 함께 다루었으며, 산업 규모에서 주로 사용되고 있는 증기개질반응과 현재 연구단계에서 발전하고 있는 촉매산화법을 비교하였다. 이 총설에서는 바이오가스로부터 메탄올전환의 가능성이 기술적인 측면과 경제적 실용성 면에서 제시되었다.

• 한국응용과학기술학회지
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• 제20권4호
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• pp.289-295
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• 2003

Synthesis gas is produced commercially by a steam reforming process. However, the process is highly endothermic and energy intensive. Thus, this study was conducted to produce synthesis gas by the partial oxidation of methane to cut down the energy cost. Supported Ni catalysts were prepared by the impregnation method. To examine the activity of the catalysts, a differential fixed bed reactor was used, and the reaction was carried out at $750{\sim}850^{\circ}C$ and 1 atm. The fresh and used catalysts were characterized by XRD, XPS, TGA and AAS. The highest catalytic activity was obtained with the 13wt% Ni/MgO catalyst, with which methane conversion was 81%, and $H_2$ and CO selectivities were 94% and 93%, respectively. 13wt% Ni/MgO catalyst showed the best $MgNiO_2$ solid solution state, which can explain the highest catalytic activity of the 13wt% Ni/MgO catalyst.

• 한국재료학회지
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• 제27권7호
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• pp.392-397
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• 2017

Fluorine-doped tin oxide (FTO) coated NiCrAl alloy foam is fabricated using ultrasonic spray pyrolysis deposition (USPD). To confirm the influence of the FTO layer on the NiCrAl alloy foam, we investigated the structural, chemical, and morphological properties and chemical resistance by using USPD to adjust the FTO coating time (12, 18, and 24 min). As a result, when an FTO layer was coated for 24 min on NiCrAl alloy foam, it was found to have an enhanced chemical resistance compared to those of the other samples. This improvement in the chemical resistance of using USPD NiAlCr alloy foam can be the result of the existence of an FTO layer, which can act as a protection layer between the NiAlCr alloy foam and the electrolyte and also the result of the increased thickness of the FTO layer, which enhances the diffusion length of the metal ion.

• Korean Chemical Engineering Research
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• 제45권4호
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• pp.319-327
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• 2007

소각은 유기성 유해폐기물에 대해 가장 발달된 유용한 처리기술로 인정되어 왔다. 그러나 PCBs와 같이 유해한 폐기물의 처리를 위한 소각로의 부지확보나 인허가가 유해한 대기오염 물질의 배출에 대한 주민의 우려로 용이하지 않다. 최근에 많은 소각 대체기술들이 개발되어 왔으며 이 기술들은 소각에 비해 다이옥신이나 퓨란과 같은 유해한 물질의 배출이 적어 주민의 우려를 완화시킬 수 있다. 본 논문에서는 다양한 유해폐기물의 종류에 대해 현재 적용이 가능한 소각 대체기술들을 검토하였다. 다양한 범주의 비열처리 및 열처리 소각 대체기술들을 공정운전조건, 적용대상 폐기물 및 이차폐기물 발생특성의 관점에서 평가하고 몇 가지 소각 대체기술들에 대해서는 공정의 운전원리에 대해 자세히 설명하였다.

• 청정기술
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• 제20권1호
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• pp.88-94
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• 2014

경유는 연료전지 시스템의 연료원으로써 주목받고 있는 탄화수소 액체연료 중 하나로, 연료개질 촉매와 연료전지의 전극재료를 피독시키는 황화합물을 포함하고 있어 탈황공정이 필요한 것으로 여겨지고 있다. 다양하고도 대안적인 탈황기술이 연구되고 있으나, 초저유황 경유의 탈황 연구는 여전히 부진한 실정이다. 본 연구는 용융탄산염 연료전지 시스템에 응용될 수 있는 원료인 상용초저유황 경유의 탈황에 관한 것이다. 여기서 초저유황의 흡착탈황을 위한 흡착제로 활성탄, 제올라이트, 금속산화물 계 상용흡착제 후보군이 선정되었고 유망한 탈황제를 찾기 위한 스크리닝 평가를 실시하였다. 그 결과 초저유황 경유의 황농도를 0.1 ppmw 수준까지 떨어뜨리기 위한 흡착제 종류로 금속산화물계가 매우 유용하며, 활성탄과 제올라이트 흡착제는 같은 실험조건에서 해당 수준의 황 농도에 이르지 못하는 것으로 나타났다.

• 한국수소및신에너지학회논문집
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• 제26권5호
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• pp.402-408
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• 2015

In D-T fusion reaction, $D_2$ (duterium) and $T_2$(tritium) are used as fuel gas. The exhaust gas of nuclear fusion includes hydrogen isotopes $Q_2$ (Q means H, D or T), tritiated components ($CQ_4$ and $Q_2O$), CO, $CO_2$, etc. All of hydrogen isotopes should be recovered before released to the atmosphere. This study focused on the recovery of hydrogen isotopes from $CQ_4$ and $Q_2O$. Two kinds of experiments were conducted to investigate the catalytic reaction characteristics of SMR (Steam Methane Reforming) and WGS (Water Gas Shift) reactions using Pt catalyst. First test was performed to convert $CH_4$ into $H_2$ using 6% $CH_4$, 6% CO/Ar feed gas. In the other test, 100% CO gas was used to convert $H_2O$ into $H_2$ at various reaction conditions (reaction temperature, S/C ratio, GHSV). As a result of the first test, $CH_4$ and CO conversion were 41.6%, 57.8% respectively at $600^{\circ}C$, S/C ratio 3, GHSV $2000hr^{-1}$. And CO conversion was 72% at $400^{\circ}C$, S/C ratio 0.95, GHSV $333hr^{-1}$ in the second test.

• 대한환경공학회지
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• 제29권5호
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• pp.528-532
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• 2007

탄화수소계열의 연료로부터 고순도 수소를 생산하는 것은 연료전지의 효율적인 운전과 밀접하다. 일반적으로 대부분의 탄화수소연료에서 수소를 생산하는 과정은 수소, 일산화탄소, 이산화탄소와 수증기혼합물이 생성되는 개질과정 및 일산화탄소를 저감하는 전이반응과 선택적 산화반응 과정으로 구성되어있다. 전이반응은 일산화탄소를 이산화탄소로 전환하는 동시에 수소가 생성되는 고온전이와 저온전이로 구성된 두 단계의 촉매전환 공정이다. 전이반응은 개질가스를 고온전이 반응에서 일산화탄소를 $3\sim4%$까지 낮추며 저온전이 반응에서 0.5%까지 저감한다. 본 연구에서 개질가스 중 일산화탄소를 0.5% 이하로 저감하기 위하여 전이반응기 설계 및 실험을 진행하였다.