• Journal of the Korean Society of Marine Environment & Safety
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• v.7 no.1
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• pp.7-14
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• 2001

The amount of petroleum consumption has been Increased according to the industrialization and It leads to the increase of the possibility of marine oil pollution. In Korea, some countermeasures including oil skimmer, gelling agent and herding agent of oil have been used for the remediation of the pollution. However, most of them have lets of shortcomings in the application under in-situ condition, because they are sensitive to the situation such as geographical feature, the wind and the tide. In reported literature, the natural powdered oil absorbent which is made of peat moss is an effective mean to clean spilled oil from lake or coast. However, the peat moss is a natural resource which is only Produced from a specific cold weather are like Canada. This indicates that the alternative materials which is readily obtained from everywhere are needed for powdered oil absorbent. Therefore. in the study, same natural materials including pine leaves and straw are tested as the alternative materials for the absorbent. The raw materials were dried and treated by heat at various temperature during several Periods and then. shattered by a grain cracking machine. The oil sorption capacity of the prepared materials was compared according to the methods of heat treatment and their sizes. The proportion of hydrogen cyanide to combustion of the absorbents was measured to confirm their final disposal methods. The biodegradability test of the absorbents was carried our to evaluate possibility of a side pollution in the coast. In was found that the heat treatment of pine leaves enhanced the capacity of oil sorption and decreased the water sorption. The maximum oil sorption was observed for the material treated at 18$0^{\circ}C$for 60 min. The amount of hydrogen cyanide from the combustion were 0.09ml/g, 0.07ml/g for pine leaves and straw respectively meaning that the final disposal by combustion might be feasible. The amount or organic carbon extracted from pine leaves during 7 days was up to 0.015g organic carbon from one gram of pine leaves. but the degradation was as fast as for glucose. It is concluded that the pine leaves can be served as a good raw material for the powdered oil absorbent like peat moss.

• Electrical & Electronic Materials
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• v.1 no.1
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• pp.70-77
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• 1988

This paper describes the influence of the electrode materials, moisture content, electrolyte density, temperature, surface state, ion absorbent on the C.T.I of phenolic resin by the I.E,C, 112 method. C.T.I are increased for electrode materials with low hydrogen overvoltage and high soluble point. Increusing moisture content of samples increased by logarithmical on the droplet number to tracking breakdown. Increasing electrolyte temperature region above 70-80(.deg.C) decreased hydrogen over-voltage, following the density changes are decreased by C.T.I=1/aD$^{2}$-bD+C.

• Journal of Hydrogen and New Energy
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• v.24 no.2
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• pp.150-159
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• 2013

To enhance the performance of SEWGS system by holding the WGS catalyst in a SEWGS reactor using bed inserts, effects of insert geometry and shape of WGS catalysts on CO conversion were measured and investigated. Small scale fluidized bed reactor was used as experimental apparatus and WGS catalyst (particle and tablet) and sand were used as bed materials. The parallel wall type and cross type bed inserts were used to hold the WGS catalysts. The CO conversion with steam/CO ratio was determined based on the exit gas analysis. The measured CO conversion using the bed inserts showed high value comparable to physical mixing cases. Moreover, gas flow direction was confirmed by bed pressure drop measurement for each case. Most of input gas flowed through the catalyst side when we charged tablet type catalyst into the bed insert and this can cause low $CO_2$ capture efficiency because the possibility of contact between input gas and $CO_2$ absorbent is low in this case. New bed insert geometry was proposed based on the results from this study to enhance contact between input gas and WGS catalyst and $CO_2$ absorbent.

• Applied Chemistry for Engineering
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• v.27 no.3
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• pp.265-269
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• 2016

Ammonia gas as a hydrogen source has received great attention since the importance of hydrogen gas as a clean energy source increased. However, ammonia is toxic and corrosive to metal such that the absorbent that can store and transport ammonia became an important issue. As an effort to solve this, a large pored covalent organic framework, COF-10 was proposed as an adsorbent for storage and safe transportation of ammonia. During the ammonia adsorption process, boron in COF-10 structure can act as a Lewis acid site and bind with ammonia. In this study, COF was synthesized and its structure was identified by BET, XRD and FT-IR. The adsorption characteristics of COF were investigated by TPD and adsorption isotherm. The COF-10 showed an excellent adsorption capacity for ammonia (9.79 mmol/g) which could be utilized as an ammonia adsorbent.

• Journal of Hydrogen and New Energy
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• v.24 no.6
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• pp.535-542
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• 2013

To enhance the performance of SEWGS system by holding the WGS catalyst in a SEWGS reactor using bed inserts, effect of bed insert geometry on CO conversion of WGS catalyst was measured and investigated. Small scale fluidized bed reactor was used as experimental apparatus and tablet shaped WGS catalyst and sand particle were used as bed materials. The cylinder type and the spring type bed inserts were used to hold the WGS catalysts. The CO conversion of WGS catalyst with the change of steam/CO ratio was determined based on the exit gas analysis. Moreover, gas flow direction was confirmed by bed pressure drop measurement for each case. The measured CO conversion using the bed inserts showed high value comparable to previous results even though at low catalyst content. Most of input gas flowed through the bed center side when we charged tablet type catalyst into the cylinder type bed insert and this can cause low $CO_2$ capture efficiency because the possibility of contact between input gas and $CO_2$ absorbent is low in this case. However, the spring type bed insert showed good reactivity and good distribution of gas, and therefore, the spring type bed insert was selected as the best bed insert for SEWGS process.

• Journal of Hydrogen and New Energy
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• v.23 no.4
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• pp.337-345
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• 2012

To check effects of operating variables on reaction characteristics of WGS catalyst for SEWGS process, water gas shift reaction tests were carried out in a pressurized fluidized bed reactor using commercial WGS catalyst and sand(as a substitute for $CO_2$ absorbent) as bed materials. Simulated syngas(mixed with $N_2$) was used as a reactant gas. Operating temperature was $210^{\circ}C$ and operating pressure was 20 bar. WGS catalyst content, steam/CO ratio, gas velocity, and syngas concentration were considered as experimental variables. CO conversion increased as the catalyst content and steam/CO ratio increased. CO conversion at fluidized bed condition was higher than that of fixed bed condition. However, CO conversion were maintained almost same value within the fluidized bed condition. CO conversion decreased as the syngas concentration increased. The optimum operation condition was confirmed and long time water gas shift reaction test up to 24 hours at the optimum operating conditions was carried out.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.134-134
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• 2010

Fuel cell is a device that directly converts chemical energy in the form of a fuel into electrical energy by way of an electrochemical reaction. In the anode for a high temperature fuel cell, nickel or nickel alloy has been used in consideration of the cost, oxidation catalystic ability of hydrogen which is used as fuel, electron conductivity, and high temperature stability in reducing atmosphere. Most MCFC stacks currently operate at an average temperature of $650^{\circ}C$. There is some gains with decreased temperature in MCFC to diminish the electrolyte loss from evaporation and the material corrosion, which could improve the MCFC life. However, operating temperature has a strong related on a number of electrode reaction rates and ohmic losses. Baker et al. reported the effect of temperature (575 to $650^{\circ}C$). The rates of cell voltage loss were 1.4mV/$^{\circ}C$ for a reduction in temperature from 650 to $600^{\circ}C$, and 2.16mV/$^{\circ}C$ for a decrease from 600 to $575^{\circ}C$. The two major contributors responsible for the change in cell voltage with reducing operation temperature are the ohmic polarization and electrode polarization. It appears that in the temperature range of 550 to $650^{\circ}C$, about 1/3 of the total change in cell voltage with decreasing temperature is due to an increase in ohmic polarization, and the electrode polarization at the anode and cathode. In addition, the oxidation reaction of hydrogen on an ordinary nickel alloy anode in MCFC is generally considered to take place in the three phase zone, but anyway the area contributing to this reaction is limited. Therefore, in order to maintain a high performance of the fuel cell, it is necessary to keep this reaction responsible area as wide as possible, that is, it is needed to keep the porosity and specific surface area of the anode at a high level. In this study effective anodes are prepared for low temperature MCFC capable of enhancing the cell performance by using zirconium hydride at least in part of anode material.