• Transactions of the Korean hydrogen and new energy society
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• v.12 no.4
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• pp.277-285
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• 2001

We developed a compact, 10 kWe, purifier-integrated reformer which supplies hydrogen for fuel cell vehicles. Our proprietary technologies regarding hydrogen purification by palladium alloy membrane and catalytic combustion by noble metal coated wire-mesh catalyst were combined with the conventional methanol steam reforming technology, resulting in higher conversion, excellent quality of product hydrogen, and better thermal efficiency than any other systems. In this system, steam reforming, hydrogen purification, and catalytic combustion take place all in a single reactor so that the whole system is compact and easy to operate. The module produces $8.2Nm^3/hr$ of 99.999% or higher purity hydrogen with CO impurity less than 10 ppm, which is equivalent to 10 kWe when PEMFC has 45 % efficiency. Thermal efficiency of the module is 81 % and the power density of the module is 1.6 L/kWe. As the results of experiments, cold-start time has been measured about 20 minutes. Response time of hydrogen production to the change of the feed rate has been within 1 minutes.

• Journal of the Korean Institute of Gas
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• v.26 no.5
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• pp.16-21
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• 2022

The reaction rate of a catalyst for producing hydrogen using the methanol steam reforming reaction was studied. It was prepared by impregnating copper, which is often used in methanol synthesis, as the main active metal, using hydrotalcite, which has excellent porosity and thermal stability, high specific surface area, weak Lewis acid point, and basicity, as a support. Activation energy and Pre-exponential factors were identified. In this study, the activation energy of the hydrotalcite catalyst impregnated with 20 wt% copper was calculated to be 97.4 kJ/mol and the Pre-exponential was 5.904 × 10¹⁰. Process simulation was performed using the calculated values and showed a similar tendency to the experimental results.

• Journal of the Korean Institute of Gas
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• v.27 no.1
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• pp.78-85
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• 2023

Fixed-bed reactor Computational Fluid Dynamics (CFD) simulation of methanol steam reforming reaction was performed using the intrinsic kinetic data of the copper-impregnated hydrotalcite catalyst. The activation energy of the copper hydrotalcite catalyst obtained from the previous study results was 97.4 kJ/mol, and the pre-exponential was 5.904 × 10¹⁰. Process simulation was performed using the calculated values and showed a similar tendency to the experimental results. And the conversion rate according to the change of the reaction temperature (200 - 450 ℃) and the molar ratio of methanol and water was observed using the intrinsic kinetic data. In addition, mass and heat transfer phenomena analysis of a commercial reactor (I.D. 0.05 - 0.1m, Length 1m) was predicted through axial 2D Symmetry simulation using the power law model of the above kinetic constants.

• Journal of the Korean Society of Marine Environment & Safety
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• v.30 no.2
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• pp.239-251
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• 2024

In this study, a hydrogen fuel cell process based on methanol was developed to reduce greenhouse gas emissions. In Case1, the methanol fuel engine system was designed to investigate the emission of exhaust gas when methanol was supplied as fuel instead of gasoline to the engine. In Case2, a hydrogen fuel cell system was designed by adding a methanol reforming system to Case1. This hybrid system produced gray hydrogen and combined the output of the engine and fuel cell to drive the ship. However, gray hydrogen emits carbon in the process of producing hydrogen. To address this problem, a carbon capture and utilization (CCU) system was added to Case3. The CO2 of the flue gas discharged from Case2 was synthesized with gray hydrogen to produce blue methanol. The results of the case studies revealed that the optimal operating conditions were 220 ℃, 500 kPa, SCR = 1.0, and flow ratio = 0.7. The system of Case3 reduced carbon emissions by 42% compared with that Case1. Thus, the hybrid system of Case3 could considerably reduce the ship's CO2 emissions.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.3
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• pp.173-179
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• 2016

This is a numerical study on the curved channel type of hydrogen reformer using the commercial code of fluid dynamics. We numerically compared the numerical model in a previous study model and the modelling of a tube type curved channel. In the result of numerical analysis on 4 types of curved channel reformers, the methanol conversion efficiency of type 1~4 were 45.0%, 45.3%, 45.6%, 45.6% respectively, and there was hardly any difference by ${\pm}0.6%$. In light of flow characteristics, the rectangle type tube and the type 2 with $45^{\circ}$ turn showed most uniform flow characteristics and concentration distribution of methanol, and the circular type tube and the type 3 with $90^{\circ}$ turn had most un-uniform flow characteristics and concentration distribution of methanol. We concluded that the design for curved channel reformer has to have rectangle type tube with curve of almost $45^{\circ}$ as in the type of curved pipe with $45^{\circ}$ turn.

• Transactions of the Korean hydrogen and new energy society
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• v.31 no.5
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• pp.411-418
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• 2020

A reformer is a device for producing hydrogen used in fuel cells. Among them, methanol steam reformer uses methanol as fuel, which is present as a liquid at room temperature. It has the advantage of low operating temperature, high energy density, and high hydrogen production. The purpose of this study is to improve the internal flow of the pressure vessel when a bundle of methanol steam reformer in the pressure vessel goes out to a single outlet. An analysis of equilibrium reaction to methanol steam reforming reaction was conducted using Aspen HYSYS^® (Aspen Technology Inc., Bedford, USA), and based on the results, computational analysis was conducted using ANSYS Fluent^® (ANSYS, Inc., Canonsburg, USA). For comparison of the results, the height of the pressure vessel, outlet diameter, and fillet was set as variables, and the optimum geometry was selected by comparing the effects of gravity and the amount of negative pressure.

• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.3-8
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• 2008

Effect of external heating rate on the conversion efficiency for the steam reforming of methanol is investigated numerically considering both heat and mass transfer of the species in a packed bed microreactor. In a results from the numerical simulation, the conversion efficiency of methanol has been obtained for the external heating rate. The axial variation of mole fraction of methanol has been additionally presented for several cases of external heating rates. The results show that for the constant inlet temperature condition the conversion efficiency of methanol increases with external heating rate over the range of operating conditions.

• Applied Chemistry for Engineering
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• v.7 no.2
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• pp.261-268
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• 1996

Various $Cu/SiO_2$ catalysts with copper concentration ranging from 0 to 50wt% were prepared by kneading method for the steam reforming of methanol. These catalysts were calcined at temperatures in the range of $400^{\circ}C{\sim}900^{\circ}C$ and then reduced in a $H_2$ atmosphere in the range of $150^{\circ}C{\sim}350^{\circ}C$. Steam reforming of methanol was carried out at atmospheric pressure over a temperature range of $200^{\circ}C{\sim}400^{\circ}C$, steam/methanol molar ratio of 0.4~1.6 and W/F of 3~25 g.-cat.hr./mol. Characterization of the catalysts was studied using IR, BET and XRD. Using copper nitrate as a precursor for catalysts, pH in the preparation of catalysts had a great effect on the catalytic activity, but pH in the preparation of catalysts, calcination temperature, and reducing temperature in $H_2$ atmosphere had no effect on the product distribution. Optimum copper concentration, calcination temperature and reducing temperature were 40wt%, $700^{\circ}C$ and $300^{\circ}C$, respective)y. Reaction temperature for maximum $H_2$ production was $275^{\circ}C$, and the formation of methane which lowered quantity and quality of $H_2$ would be inhibited below $275^{\circ}C$. $Cu^{\circ}-Cu_2O$ might be active species in $Cu/SiO_2$ catalyst.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.467-470
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• 2006

For a mobile application such as cellular phone, micro fuel cells should be extremely compact and thin. RHFC can be an alternative solution because RHFC gives higher power density than DMFC and does not need ahydrogen storage vessel In this paper, RHFC using methanol fuel is made as a novel planar design without a PROX. Both reformer and cell are made closely in a same plate to share the heater of reformer with the cell. The PBI membrane is used in the cell. The reason is that high temperature of reformer can cause a performance drop when perfluorosulfonic acid membrane such as Nafion is used such a high temperature operation also guarantees the higher CO tolerance to MEA catalyst. The cell is designed as an air-breathing type which the cathode of the cell is opened to the air. The commercial Cu/ZnO/Al2O3 steam reformer catalyst is packed in reformer channel. The active area of MEA is $11.9cm^2$ and the peak power density was $27.5mW/cm^2$.

• Transactions of the Korean hydrogen and new energy society
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• v.13 no.2
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• pp.119-126
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• 2002

The methanol partial oxidation using commercial $CuO/ZnO/Al_2O_3$ catalysts in a plug flow reactor was studied in the temperature range of $200{\sim}250^{\circ}C$ at atmospheric pressure, It was achieved the high activities by Cu-based catalysts and the selectivity of $CO_2$/$H_2$ was 100% when $O_2$ was fully convened. The reactivity changes and their hysteresis with increasing/decreasing temperatures were observed due to the chemical state differences between the oxidation and the reduction on the Cu surface, It was suggested as the two-step reaction: the complete oxidation and the following steam reforming for methanol, which was indicated by the distributions of final products vs. the residence time. In addition, the complete oxidation step was shown to be extremely fast and the total reaction rate can be controlled by the steam reforming reaction.