• Journal of the Korean Applied Science and Technology
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• v.35 no.3
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• pp.757-767
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• 2018

In the propane dehydrogenation reaction proceeding at high temperature, the main cause of deactivation of the catalyst is coke deposition and sintering. In order to investigate the catalysts for reducing such inactivation, we have investigated the applicability of $MgAl_2O_4$ as a carrier for the catalytic dehydrogenation reaction. $MgAl_2O_4$ was prepared by Alcohthermal method at calcination temperature of 800, 900, $1000^{\circ}C$, and $Pt-Sn/MgAl_2O_4$ catalyst was prepared by supporting Pt and Sn by co-impregnation method. The reaction temperature was conducted at a high temperature of 650, $600^{\circ}C$ to confirm the thermal stability. As a result of the reaction experiment, it was confirmed that the conversion rate and yield of propane dehydrogenation reaction test were higher than that of the carrier-applied catalyst having a carrier calcination temperature of 900 and $1000^{\circ}C$, when the carrier-applied catalyst having a calcination temperature of $800^{\circ}C$ was used, It was found that the yield was higher than that of $Pt-Sn/{\theta}-Al_2O_3$ at $650^{\circ}C$. TGA, BET, XRD, CO-chemisorption, and SEM-EDS analyzes were performed for characterization. $MgAl_2O_4-800^{\circ}C$ was correlated with the relationship between good yield, Pt dispersion and low deactivation rate.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.109-112
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• 2007

유동층 반응기를 이용한 프로판의 촉매 분해는 $CO_2$를 방출하지 않고 수소를 생성하는 새로운 방식이다. 카본블랙을 이용한 프로판 분해는 메탄보다 상대적으로 분해가 잘되며, 같은 온도에서 전환률이 높기 때문에 수소 생성량이 더 많다. 촉매로 사용된 카본블랙은 반응 중 생성되는 탄소의 침적에도 불구하고 8시간 이상 촉매의 활성이 유지되어 전환율이 일정하게 유지되었다. 프로판 촉매 분해 실험은 상압에서 600 ${\sim}$ $800^{\circ}C$ 온도 변화 실험을 수행하였고, 가스 유속 변화는 2.0 ${\sim}$ $4.0U_mf$에서 실험 조건 변화에 따른 실험을 하였다. 온도, 유속 변화에 따른 생성 가스의 몰분율과 프로판 전환율을 분석하였다. 프로판 분해에 의해 생성된 기체는 수소뿐만 아니라 메탄, 에틸렌, 에탄, 프로필렌과 분해되지 않은 프로판이 배출되었다. 수소를 제외한 여타 가스들은 고온에서 실험을 할수록 몰비가 줄어들었다. 고온에서 프로판의 전환율과 수소 수득률이 증가하였다. 프로판 분해 실험 전후의 카본블랙 표면의 변화는 FE-TEM으로 관측하였다.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.57-60
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• 2007

A fluidized bed reactor made of quartz with 0.055 m I.D. and 1.0 m in height was employed for the thermocatalytic decomposition of methane to produce $CO_{2}$ - free hydrogen. The fluidized bed was proposed for the continuous withdraw of product carbons from the reactor. The methane decomposition rate with the carbon black N330 catalyst was quickly reached a quasi-steady state rate and remained for several hour. The methane and propane mixture decomposition reaction was carried out at the temperature range of 850 - 900 $^{\circ}C$, methane and propane mixture gas velocity of 1.0 $U_{mf}$ ${\sim}$ 3.0 $U_{mf}$ and the operating pressure of 1.0 atm. Effect of operating parameters such as reaction temperature, gas velocity on the reaction rates was investigated. The produced carbon by the methane decomposition was deposited on the surfaces of carbon catalysts and the morphology was observed by SEM image.

• Journal of the Korean Society of Combustion
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• v.3 no.1
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• pp.11-19
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• 1998

The influence of oxidant addition on soot formation is investigated experimentally with ethylene, propane and mixture fuel co-flow diffusion flames. Oxidant addition into fuel shows the increase of integrated soot volume fractions for ethylene, ethylene/ethane and ethylene/methane mixture flames. However, the increase of integrated soot volume fraction with oxidant addition was not significant for propane and ethylene/propane mixture flames. This discrepancy is explained with $C_2\;and\;C_3$ chemistry at the early stage of soot formation process. The oxidant addition increases the concentration of $C_3H_3$ in the soot formation region, and therefore, enhances soot formation process. A new soot formation rate model that includes both dilution effect and chemical effect of oxygen is suggested to interpret the increase of integrated soot volume fractions with oxidant addition into ethylene. Also, the role of adiabatic flame temperature for the chemical effect of oxygen addition into fuel was reviewed. The influence of oxidant or diluent addition into fuel on soot formation process are the fuel dilution effect, the adiabatic flame temperature altering effect and/or the chemical effect of oxygen. Their relative importance could change with fuel structure and adiabatic flame temperature.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.97-100
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• 2007

A fluidized bed reactor made of quartz with 0.055 m I.D. and 1.0 m in height was employed for the thermocatalytic decomposition of methane to produce $CO_2$ - free hydrogen . The fluidized bed was proposed for the continuous withdraw of product carbons from the reactor. The methane decomposition rate with the carbon black N330 catalyst was quickly reached a quasi-steady state rate and remained for several hour. The methane and propane mixture decomposition reaction was carried out at the temperature range of 850 - 900 $^{\circ}C$, methane and propane mixture gas velocity of 1.0 $U_{mf}$ ${\sim}$ 3.0 $U_{mf}$ and the operating pressure of 1.0 atm. Effect of operating parameters such as reaction temperature, gas velocity on the reaction rates was investigated. The produced carbon by the methane decomposition was deposited on the surfaces of carbon catalysts and the morphology was observed by TEM image.

• Korean Chemical Engineering Research
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• v.60 no.3
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• pp.459-467
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• 2022

Redispersion of Pt-Sn particles in Pt, PtSn catalyst which have been sintered by high temperature hydrogen reduction was investigated using oxygen treatment with various temperatures. The aim of this study was to understand the relationship between the catalytic activity for propane dehydrogenation reaction and the change in the physicochemical properties of the catalyst. X-ray diffraction analysis (XRD), CO pulse chemisorption, and H₂ temperature programmed reduction (H₂-TPR) were performed to investigate the state of active metal and interactions between particles of redispersed catalyst. It was confirmed that the dispersion and particle size of platinum, the crystal phase of the catalyst, and the reduction behavior were changed according to the oxygen treatment. As for the catalytic activity in propane dehydrogeantion, sintered PtSn catalyst treated with oxygen at 500 ℃ showed best activity and recovery of initial activity. It was confirm that catalyst after oxygen treatment at 500 ℃ showed high dispersion of Pt and decreased particle size as the results of CO pulse chemisorption and XRD of catalyst, and thus the redispersion of PtSn particles in sintered catalyst was occurred. Catalytic activity was recovered due to redispersion using oxygen treatment, and the activity recovery of the PtSn catalyst was higher than that of Pt catalyst.

• Korean Chemical Engineering Research
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• v.51 no.1
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• pp.47-52
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• 2013

In this study, the catalytic performance and characterization of $Ni/Ce_xZr_{1-x}O_2$ were investigated using an autothermal reforming (ATR) process for hydrogen production. The $Ni/Ce_xZr_{1-x}O_2$ catalysts were prepared using the following methods: the water method (CZ-W), urea water method (CZ-UW) and urea, water and ethanol method (CZ-UWA). The performance of $Ni/Ce_xZr_{1-x}O_2$ catalysts in autothermal reforming of propane for hydrogen production was studied in a fixed-bed flow reactor. Reaction tests were conducted by using a feed of $H_2O/C_3H_8/O_2$=3/1/0.37 and $300{\sim}700^{\circ}C$. The CZ-UW and CZ-UWA catalysts showed higher propane conversion and hydrogen yield than the CZ-W catalyst. The activity test confirmed that the improvement in the water-ethanol catalyst was due to the low level of carbon deposition. SEM showed that the surface carbon consisted of clusters on the used CZ-UW catalyst, which is incontrast to the nano-fiber morphology observed on the used CZ-UWA catalyst. It was found that the amount of carbon deposition depends on the preparation method. Especially the $Ni/Ce_{0.75}Zr_{0.25}O_2$ was showed higher propane conversion and hydrogen yield than the other catalysts. Also TGA showed that the resistance of carbon deposition increase to Co addition.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.1
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• pp.48-53
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• 2006

The purpose of this paper is to investigate the optimal condition of the SynGas production by reforming of propane using plasmatron. Plasma was generated by air and arc discharge. The effects of applied steam, $CO_2$ or Ni-catalyst on propane conversion, yield of hydrogen and $H_2/CO$ ratio as well as correlation of syngas were studied. When the variations of $O_2/C_3H_8$ flow ratio, $H_2O/C_3H_8$ flow ratio and $CO_2/C_3H_8$ flow ratio were $0.94{\sim}1.48,\;4.3{\sim}10\;and\;0.8{\sim}3.05$ respectively, Under the condition mentioned above, result of $H_2O/C_3H_8$ flow ratio was maximum $H_2$ concentration, or $28.2{\sim}31.6%$, and result of $H_2O/C_3H_8$ flow ratio with catalyst was minimum CO concentration or $6.6{\sim}7.1%$ and the ratio of hydrogen to carbon monoxide($H_2/CO$) were $3.89{\sim}4.86$.

• Journal of the Korean Society of Combustion
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• v.7 no.2
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• pp.24-33
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• 2002

The morphology of deposits on $15-{\mu}m$ thin SiC filaments has been investigated with SEM in a co-flowing, propane/air laminar diffusion flame. The average size of mature soot particles deposited in the luminous flame edge is strongly dependent on their axial position in a typical heavily sooting flame. The surface growth of liquid-phase PAHs molecules and the transition to soots from fully-developed precursors could be observed in the radial deposition of the flame. Two sooting regimes were found: one is the transition from the condensed-phase precursors; the other is the aggregation of smaller soot particles (or chains of them) to be carried along particle path lines. In the high temperature flame edge outside the soot luminous flame surface, the very thin fiber-like structures, which are about 10 nm thick, were found.

• Journal of ILASS-Korea
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• v.3 no.4
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• pp.35-42
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• 1998

Laser Raman scattering method has been applied to measure equivalence ratio of methane/air and propane/air mixture in constant volume combustion chamber. We used high power KrF excimer laser$(\lambda=248nm)$ and a high gain ICCD camera to capture low intensity Raman signal. Raman shifts and Ram cross-sections of $H_2,\;O_2,\;N_2,\;CO_2,\;CH_4\;and\;C_3H_8$ were measured precisely. Our results showed an excellent agreement with other groups. Mole fraction measurement of $O_2\;and\;N_2$ from air showed that $O_2\;:\;N_2$ = 0.206 : 0.794. We used constant volume combustion chamber and gas injector which is operated at $5\sim10barg$. Methane and propane are used as a fuel. 50 Raman signal are obtained and ensemble averaged for measurement of equivalence ratio. Our measured results showed that the equivalence ratio of fuel/air mixture is reasonable at ${\pm}5%$ error range.