• Journal of the Korean Applied Science and Technology
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• v.29 no.2
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• pp.339-347
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• 2012

This study focuses on developing catalysts for the removal of toluene produced from paint booth. Toluene is one of the major VOC in painting, coating process. Pd catalysts have been used in hydrogenation oxidation and low temperature combustion reaction for toluene removal. Pd catalysts, even though it is very precious and expensive. Therefore, the prepared catalysts from minimizing the amount of Pd ratio (0.1~1.0wt%) were measured. As a result, 1.0wt% Pd(R) catalyst under all conditions showed the highest activity. These results may suggest that the catalytic activity is related to Pd dispersion according sintering atmosphere and Pd ratio in the manufacturing process through the analysis of SEM, XRD.

• Journal of the Korean Society of Propulsion Engineers
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• v.15 no.6
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• pp.56-62
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• 2011

An experimental study on design of a catalytic ignitor was performed to use an ignition source for a small bi-propellant liquid rocket engine which use hydrogen peroxide and kerosene as propellants. In the catalytic ignitor, hot gas of hydrogen peroxide which was decomposed by a catalyst induced autoignition of kerosene. Mass flow rate and O/F ratio for the ignitor were calculated by CEA code. A combustion chamber which had a quartz window and thermocouples was manufactured to determine whether the ignition is successful. Ignition performance was investigated according to exit area of fixed rings and mixture ratio. Results showed that reliable ignition performance was achieved at non-choking exit area of fixed ring and O/F ratio of 6~8.

• Resources Recycling
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• v.27 no.3
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• pp.93-99
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• 2018

Effective extraction of platinum group elements by dissolving waste platinum scrap from the display industry and solvent extraction, was studied. The extracted platinum solution was prepared as a precursor solution for diesel automotive exhaust gas purification catalyst and its catalytic activity was tested. The behavior of aqueous species of platinum was investigated through solution chemistry and based on the existence and behavior of these chemical species, the possibility of extraction and separation was established. By dissolving waste scrap by electrochemical method, the dissolution time of scrap was shortened and the extraction efficiency was increased. Through separation and removal of rhodium component, solvent extraction by TBP, and stripping by hydrochloric acid, Pt-Chloride-$H_2O$ solution was prepared. And then, an platinum amine complex solution through amination reaction with this solution as a raw material was prepared. The possibility of producing high-value platinum compounds from platinum group waste scrap was investigated by preparing platinum amine complex solution and then examining the catalytic activity with this amine precursor on the combustion reaction of carbon black.

• Journal of the Korean Society of Propulsion Engineers
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• v.21 no.4
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• pp.21-27
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• 2017

In this paper, in order to control the burning rate and pressure exponent of HTPB/AP/Al based propellant for the improvement of performance, the effect of the size ratio of AP particles and various contents of Butacene as burning catalyst on combustion properties was investigated. In the propellant formulation with both $28{\mu}m$ Al of 23% and Butacene of 3%, the burning rate and pressure exponent were increased with increasing the contents of $9{\mu}m$ AP particles. And the burning rate was increased with increasing the contents of Butacene with showing the relatively low pressure exponent in the propellant containing Butacene. However, the significant variations of pressure exponent by contents of Butacene were not observed.

• Journal of Aerospace System Engineering
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• v.11 no.2
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• pp.9-15
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• 2017

In order to verify the possiblity of improving the combustion performance of ethanol using zeolite catalyst and the characteristics of nitrogen oxides and carbon monoxide emission, micro gas turbine experiments were performed using catalytic reaction products, ethanol and kerosene as fuels and the results were compared. The thrust of the catalytic reaction product was lower than that of kerosene, but it was improved by 5% on average compared with the use of ethanol. Nitrogen oxides and carbon monoxide emissions of the catalytic reaction products were measured to be very low overall compared to kerosene. As a result, when the ethanol was reformed using the zeolite catalyst, the engine performance could be improved while maintaining the environment friendliness of the ethanol.

• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.340-344
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• 2008

The importance of the more efficient cogeneration system is emphasized. Also the more clean energy is needed at recent energy system. The cogeneration system using Lean burn engine is more preferred to the system using Rich burn engine because of the electrical efficiency. Although the cogeneration system using Lean burn engine is economically preferred, because of the NOx emission level, the system using Rich burn engine with 3-way catalyst can only be used in Korea. The NOx regulation level is 50ppm at oxygen level 13%. The cogeneration hybrid system using Lean burn engine is up to be optimized because of the large amount of the extra-fuel at the after-burner system. The after-burner system at different concept was applied. The reduction time for the activation temperature of the DeNOx catalyst was achieved by making a hole between the combustor and boiler. Because of the lowered fuel consumption, the lowered temperature level was optimized by blocking the hole of the boiler The optimized cogeneration hybrid system consumes $76Nm^3/h$ LNG to produce 150kW electricity compared to before optimization $103Nm^3/h$ LNG. The system was accurately evaluated and the result is following ; 90% total efficiency, below 10 ppm NOx, 50ppm CO, 25ppm HC. The cogeneration hybrid system can meet the current NOx level and exhaust gas regulation. It can achieve the clean combustion gas and efficient cogeneration system.

• Clean Technology
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• v.22 no.4
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• pp.211-224
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• 2016

Three way catalyst has been used extensively for the exhaust gas treatment for the internal combustion gasoline engine. While, numerous research efforts have been directed to develop various technologies for the abatement of exhaust gas from diesel engine. Diesel engine operating under lean condition produces large amount of NOx and the corresponding catalytic technology employing vanadium supported titania using ammonia has been commercialized for heavy duty vehicle. Recently, the Cu catalyst supported on zeolite has been investigated for NOx abatement using ammonia because of its critical importance for ultra low emission vehicle. The current review shows the recent trend in research and development for zeolite based copper catalysts, which are mainly used as catalysts for selective catalytic reduction using ammonia, are one of the aftertreatment technologies for effectively removing nitrogen oxides from diesel exhaust.

• Clean Technology
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• v.22 no.2
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• pp.132-138
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• 2016

The emission of SO₂ is inevitable in case of combustion of most fossil fuels except LNG in commercial power plant which has a bad effect on the durability of SCR catalyst. To develop a low temperature SCR catalyst which has a high NOx removal performance and excellent durability to SO₂, V₂O₅/TiO₂ catalysts were prepared by coating on the metal foam substrate with the impregnation amount of Sb₂O₃ as promotor. This study has evaluated the NOx removal performance and the durability to SO₂ on a laboratory scale atmospheric reactor and analyzed the properties of the prepared catalysts by means of porosimeter, BET, SEM (scanning electron microscope), EDX (energy dispersive x-ray spectrometer), XPS (X-ray photoelectron spectroscopy). It was found that the surface area of catalyst increased with the impregnation amount of Sb₂O₃ and the NOx removal performance showed the highest value at the 2 wt% impregnation of Sb₂O₃. This results was considered to be due to the optimum active site on the catalyst surface. And also, Sb₂O₃ impregnated catalysts presented that NOx removal performance was maintained despite the exposure to SO₂ for 5 hours. Therefore it was confirmed that metal foam SCR catalyst for low temperature could be manufactured with the optimum control of Sb₂O₃ impregnation according to the SO₂ presence or not.

• 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.

• Korean Chemical Engineering Research
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• v.59 no.3
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• pp.435-442
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• 2021

Mn-added Barium hexaaluminates were manufactured by homogeneous precipitation method using Urea. The effects of water wash and dry temperature were analyzed by thermal weight analysis, X-ray diffraction analysis, and scanning electron microscopy. Catalysts that went through the filtration step only produced pure hexaaluminate images compared to those that went through the water wash step. During the drying process, it seems that the remaining urea helps dehydration of the precursor and affects the phase shift of gibbsite to boehmite, which is easy to convert to pure hexaaluminate. The catalyst WO200 gave the best performance in the methane combustion reaction, and NOx was not emitted in the reaction for all catalysts. Hexaaluminates were found to affect reducing the highest CO emissions.