• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.720-722
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• 2009

This work is mainly focused at developing the hydrogen production unit with the capacity of 20 $Nm^3/h$ of high purity hydrogen. At present steam reforming of natural gas is the preferable method to produce hydrogen at the point of production cost. The developed hydrogen production unit composed of natural gas reformer and pressure swing adsorption system. To improve the thermal efficiency of steam reforming reactor, the internal heat recuperating structure was adopted. The heat contained in reformed gas which comes out of the catalytic beds recovered by reaction feed stream. These features of design reduce the fuel consumption into burner and the heat duty of external heat exchangers, such as feed pre-heater and steam generator. The production rate of natural gas reformer was 41.7 $Nm^3/h$ as a dryreformate basis. The composition of PSA feed gas was $H_2$ 78.26%, $CO_2$ 18.49%, CO 1.43% and $CH_4$ 1.85%. The integrated production unit can produce 21.1 $Nm^3/h$ of high-purity hydrogen (99.997%). The hydrogen production efficiency of the developed unit was more than 58% as an LHV basis.

• 공업화학
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• 제19권5호
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• pp.466-470
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• 2008

본 연구에서는 가연성 폐기물에서 발생되는 합성가스 내 $CH_4$를 나노기공성 촉매를 사용하여 $H_2$로 전환하고자 하였다. 이때 사용된 나노기공성 촉매는 $Ni/Al_2O_3$ 촉매를 one-pot 방법으로 제조하여 사용하였다. 촉매의 분석 결과, 삼차원으로 연결된 스폰지 모양을 갖는 입자가 형성되었으며, 구형의 상용 촉매보다 넓은 표면적과 작은 입자크기, 균일한 기공 크기의 특성을 지닌 나노기공성 촉매가 제조된 것을 확인할 수 있었다. $CH_4$ 개질반응에 사용된 $Ni/Al_2O_3$ 촉매의 Ni 최적 담지량은 16 wt%였으며 $750^{\circ}C$에서 $CH_4$ 전환율 91%, $CO_2$ 전환율 92%로 가장 높은 전환율을 나타냈다. 또한, 상용 알루미나를 사용하여 제조한 촉매와의 성능 비교 결과 자체 제조한 촉매가 약 20% 향상된 전환율을 나타냈다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2015년도 제51회 KOSCO SYMPOSIUM 초록집
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• pp.73-74
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• 2015

Synthesis gas such as hydrogen and carbon monoxide was produced from $CH_4/oxygen$ mixture using insulated pressurized porous media combustor. Experimentally, two cylindrical SiC foams with the different pore density were piled up in a quartz tube and fully premixed mixture was supplied in the axial direction. After stabilizing fuel-rich flame at the interface of the two foams at several pressure conditions, mole fractions of synthesis gases were measured by gas chromatography. Heat recirculation through the inner foam structure could extend the flow velocity of stable region over the laminar burning velocity. As the pressure increased, the rich flammability limit, $H_2/CO$ ratio, and module M increased.

• 청정기술
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• 제29권4호
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• pp.327-332
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• 2023

본 연구에서는 바이오가스 수증기 개질을 통한 합성가스 생산에 관해 연구했다. Ni-Al₂O₃ 및 Ni-CeO₂ 촉매는 공침법으로 제조되었으며 침전제 주입 속도가 조절되었다. 온도에 따른 촉매 성능 테스트는 CH₄:CO₂:H₂O = 1:0.67:3의 가스 조성비와 647,000 mL h^-1 gcat^-1의 공간속도에서 진행하였다. 침전제 주입 속도는 촉매 특성에 영향을 미쳤으며, 지지체 종류에 따라 결과를 보였다. 온도가 증가함에 따라 이산화탄소 개질 반응과 reverse water gas shift 반응이 일어났다. 수증기가 충분히 공급되는 조건에서는 침전제를 한 번에 투입하여 제조된 Ni-Al₂O₃ 촉매가 높은 Ni 분산도에 기인하여 가장 우수한 성능을 보였다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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• pp.249-251
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• 2014

Synthesis gas such as hydrogen and carbon monoxide was produced from $CH_4//oxygen$ mixture using two-section porous media combustor. Heat recirculation through the inner foam structure could extend the flow velocity of stable region over the laminar burning velocity. $H_2/CO$ ratio and module M from concentration of flue gas measured by Gas Chromatography was similar to those calculated by equilibrium. But it was made sure that the heat loss effect becomes more influential than heat recirculation effect as the mixture gets richer. To generate synthesis gas appropriate for methanol production, insulated pressurized porous media combustor will be designed and built in the future.

• 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.

• 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.

• 공업화학
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• 제18권6호
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• pp.618-624
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• 2007

Cu/Fe/Zr 혼합 산화물 매체 상에서의 2단계 열화학 메탄 개질 반응을 고정층 적외선 반응로를 이용하여 수행했다. 첫 번째 단계에서 금속 산화물은 CO, $H_2$ 및 환원된 금속 산화물을 생성하기 위하여 1173 K의 온도에서 메탄으로 환원되었다. 두번째 단계에서 환원된 금속 산화물은 $H_2$와 금속 산화물을 생성하기 위하여 973 K의 온도에서 재산화되었다. 본 연구에서는 Cu/Fe/Zr 혼합 산화물 내 Cu 첨가량에 따른 반응 특성과 사이클 반응을 평가하였다. Cu/Fe/Zr 혼합 산화물 매체 내 Cu 첨가량 증가에 따라 첫 번째 단계에서 $CH_4$ 전환율, $CO_2$로의 선택성 및 $H_2/CO$ 몰 비는 증가하였으며, CO로의 선택성은 감소하는 경향을 나타냈다. 한편, 두 번째 단계에서 $H_2$ 생성량은 Cu 첨가량 증가에 따라 감소하는 것으로 나타났다. Cu의 첨가량이 x = 0.7인 $Cu_xFe_{3-x}O_4/ZrO_2$ 매체는 내구성이 우수한 매체임을 지시하듯이 10회의 사이클 순환 반응에서 우수한 재생 성능을 나타냈다. 더 나아가 물 분해 단계에서 침적된 탄소의 가스화 반응은 매체 내 Cu 첨가에 의해 촉진되었다.

• 한국수소및신에너지학회논문집
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• 제26권5호
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• pp.445-452
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• 2015

A tubular packed bed reactor for the steam-$CO_2$ combined reforming of natural gas to produce the synthesis gas of a target $H_2/CO$ ratio 2.0 was simulated. The effects of the reactor dimension, the feed gas composition, and the gas feeding temperature upon the possibility of coke formation across the catalyst bed were investigated. For this purpose, 2-dimensional heterogeneous reactor model was used to determine the local gas concentrations and temperatures over the catalyst bed. The thermodynamic potential distribution of coke formation was determined by comparing the extent of reaction with the equilibrium constant given by the reaction, $CH_4+2CO{\Leftrightarrow}3C+2H_2O$. The simulation showed that catalysts packed in the central region nearer the entrance of the reactor were more prone to coking because of the regional characteristics of lower temperature, lower concentration of $H_2O$, and higher concentration of CO. With the higher feeding temperature, the feed gas composition of the increased $H_2O$ and correspondingly decreased $CO_2$, or the decrease in the reactor diameter, the volume fraction of the catalyst bed subsequent to coking could be diminished. Throughout the simulation, reactor dimension and reaction condition for coking-free operation were suggested.

• 한국수소및신에너지학회논문집
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• 제20권6호
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• pp.519-525
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• 2009

The catalytic steam reforming of woody biomass tar and soot to convert a synthetic gas containing hydrogen was investigated by using a bench-scale biomass gasification system. One commercial nickel-based catalyst, Katalco 46-6Q, and two different kinds of natural minerals, dolomite and olivine, were tested as a reforming catalyst at various reforming temperatures. The reaction characteristics of woody biomass tar were also investigated by TGA at a variety of heating rates. With all three catalysts conversion efficiency of tar and soot increased at increasing temperature. The reforming of tar and soot in the synthetic gas induce the increase of combustible gases such as $H_2$, CO and $CH_4$ in the product gas. The nickel-based catalyst showed a higher tar and soot conversion efficiency than mineral catalysts under the same temperature conditions.