• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.157.2-157.2
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• 2011

In this work, we prepared Mg nanoparticles loaded graphite oxide (Mg-G) as a function of Mg content in order to investigate hydrogen storage behaviors. The structure and morphology of the Mg-G samples were characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). The textural properties of the samples were evaluated using $N_2$/77 K adsorption isotherms. The hydrogen adsorption capacities were investigated at 298 K/10 MPa. As a result, the hydrogen adsorption capacities of the Mg-G were enhanced with increasing the Mg content. Therefore, it was found that the presence of Mg on graphite surfaces created hydrogen-favorable sites, resulting in enhancing the hydrogen adsorption capacity.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.304-304
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• 2009

In this study, the adsorption behaviors of mercury ions on the electroless Cu-plated activated carbons have been investigated. The amount of copper on activated carbons have been confirmed by atomic absorption spectrophotometer (AAS). The surface properties of the ACs studied have been characterized by using Boehm's titration method and scanning electron microscopy (SEM).Experimental results showed the adsorption capacity of mercury ions was increased as the electroless Cu plating. This was probably due to the introduction of copper on ACs leaded to an increase in the surface basicity.

• Journal of Pharmaceutical Investigation
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• v.18 no.3
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• pp.133-137
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• 1988

In vitro studies were performed on the interaction of indomethacin with cholestyramine, a hypocholesterolemic substance. Cholestyramine showed a marked affinity for indomethacin among tested acidic drugs and the intensity of adsorption was dependent on pH, temperature and sodium chloride. Moreover, the combination of indomethacin with some acidic drugs that formed complexes with cholestyramine, considerably inhibited the adsorption of indomethacin on the resin.

• Carbon letters
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• v.15 no.4
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• pp.295-298
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• 2014

In this work, nanoporous carbons (NPCs) were prepared by the self-assembly of polymeric carbon precursors and block copolymer template in the presence of tetraethyl orthosilicate and colloidal silica. The NPCs' pore structures and total pore volumes were analyzed by reference to $N_2$/77 K adsorption isotherms. The porosity and elemental mercury adsorption of NPCs were increased by activation with carbon dioxide. It could be resulted that elemental mercury adsorption ability of NPCs depended on their specific surface area and micropore fraction.

• Journal of the Korean Vacuum Society
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• v.21 no.2
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• pp.106-112
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• 2012

New equipment for quantitative and qualitative adsorption of volatile organic compound was set up, and using this equipment, adsorption behaviors of various carbob-based nanomaterials and $TiO_2$ thin films prepared by atomic layer deposition were compared. We could conclud that $TiO_2$ thin films can show higher adsorption capacity of toluene comparing to the carbon-based nanostructures due to higher affinity of the surface OH groups of $TiO_2$ towards toluene adsorption. We also demonstrate that our method allows to discriminate reversible and irreversible adsorptions at a given temperature.

• Carbon letters
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• v.4 no.1
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• pp.31-35
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• 2003

The specific adsorption behaviors of activated carbons (ACs) treated with 30 wt% $H_3PO_4$ or NaOH were investigated in the removals of NO or $NH_3$. The acid and base values were determined by Boehm's titration method. And, the surface properties of ACs were studied by FT-IR and XPS analyses. Also, $N_2/77K$ adsorption isotherm characteristics, including the specific surface area and micropore volume were studied by BET and t-plot methods, respectively. From the adsorption tests of NO and $NH_3$, it was revealed in the case of acidic treatment on ACs that the $NH_3$ removal was more effective due to the increase of acidic functional groups in carbon surfaces. Also, the NO removal was increased, in the case of basic treatment, due to the improvement of basic functional groups, in spite of significant decreases of BET's specific surface area and total pore volume. It was found that the adsorption capacity of ACs was not only determined by the textural characteristics but also correlated with the surface functional groups in the acid-base intermolecular interactions.

• Journal of the Mineralogical Society of Korea
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• v.11 no.1
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• pp.20-31
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• 1998

Adsorption of metal elements onto illite and halloysite was investigated at $25^{\circ}C$ using pollutant water collected from the gold-bearing metal mine. Incipient solution of pH 3.19 was reacted with clay minerals as a function of time: 10 minute, 30 minute, 1 hour, 12 hour, 24 hour, 1 day, 2 day, 1 week, and 2 week. Twenty-seven cations and six anions from solutions were analyzed by AAs (atomic absorption spectrometer), ICP(induced-coupled plasma), and IC (ion chromatography). Speciation and saturation index of solutions were calculated by WATEQ4F and MINTEQA2 codes, indicating that most of metal ions exist as free ions and that there is little difference in chemical species and relative abundances between initial solution and reacted solutions. The adsorption results showed that the adsorption extent of elements varies depending on mineral types and reaction time. As for illite, adsorption after 1 hour-reaction occurs in the order of As>Pb>Ge>Li>Co, Pb, Cr, Ba>Cs for trace elements and Fe>K>Na>Mn>Al>Ca>Si for major elements, respectively. As for halloysite, adsorption after 1 hour-reaction occurs in the order of Cu>Pb>Li>Ge>Cr>Zn>As>Ba>Ti>Cd>Co for trace elements and Fe>K>Mn>Ca>Al>Na>Si for major elements, respectively. After 2 week-reaction, the adsorption occurs in the order of Cu>As>Zn>Li>Ge>Co>Ti>Ba>Ni>Pb>Cr>Cd>Se for trace elements and Fe>K>Mn>Al, Mg>Ca>Na, Si for major elements, respectively. No significant adsorption as well as selectivity was found for anions. Although halloysite has a 1:1 layer structure, its capacity of adsorption is greater than that of illite with 2:1 structure, probably due to its peculiar mineralogical characteristics. According to FTIR (Fourier transform infrared spectroscopy) results, there was no shift in the OH-stretching bond for illite, but the ν1 bond at 3695 cm-1 for halloysite was found to be stronger. In the viewpoint of adsorption, illite is characterized by an inner-sphere complex, whereas halloysite by an outer-sphere complex, respectively. Initial ion activity and dissociation constant of metal elements are regarded as the main factors that control the adsorption behaviors in a natural system containing multicomponents at the acidic condition.

• Bulletin of the Korean Chemical Society
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• v.16 no.6
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• pp.498-503
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• 1995

The adsorption behaviors of two major components purified, endo Ⅱ and exo Ⅱ, from Trichoderma viride were investigated using microcrystalline cellulose with different specific surface area as substrates. Adsorption was found to apparently obey the Langmuir isotherm and the thermodynamic parameters, ΔH, ΔS, and ΔG, were calculated from adsorption equilibrium constant,K. The adsorption process was found to be endothermic and an adsorption entropy-controlled reaction. The amount of adsorption of cellulase components increased with specific surface area and decreased with temperature and varied with a change in composition of the cellulase components. The maximum synergistic degradation occurred at the specific weight ratio of the cellulase components at which the maximum affinity of cellulase components obtains. The adsorption entropy and enthalpy for respective enzyme system increased with specific surface area increase. The adsorption entropy was shown to have a larger value with enzyme mixture.

• Bulletin of the Korean Chemical Society
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• v.32 no.4
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• pp.1321-1326
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• 2011

In this work, the effects of different surface functional groups on the elemental mercury adsorption of porous carbons modified by chemical treatments were investigated. The surface properties of the treated carbons were observed by Boehm's titration and X-ray photoelectron spectroscopy (XPS). It was found that the textural properties, including specific surface area and pore structures, slightly decreased after the treatments, while the oxygen content of the ACs was predominantly enhanced. Elemental mercury adsorption behaviors of the acidtreated ACs were found to be four or three times better than those of non-treated ACs or base-treated ACs, respectively. This result indicates that the different compositions of surface functional groups can lead to the high elemental mercury adsorption capacity of the ACs. In case of the acid-treated ACs, the $R_{C=O}/R_{C-O}$ and $R_{COOH}/R_{C-O}$ showed higher values than those of other samples, indicating that there is a considerable relationship between mercury adsorption and surface functional groups on the ACs.

• Bulletin of the Korean Chemical Society
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• v.35 no.1
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• pp.57-61
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• 2014

In this study, carbon aerogel (CA) was synthesized using a soft-template method, and the optimum conditions for the adsorption of carbon dioxide ($CO_2$) by the carbon aerogel were evaluated by controlling the activation temperature. KOH was used as the activation agent at a KOH/CA activation ratio of 4:1. Three types of activated CAs were synthesized at activation temperatures of $800^{\circ}C$(CA-K-800), $900^{\circ}C$(CA-K-900), and $1000^{\circ}C$(CA-K-1000), and their surface and pore characteristics along with the $CO_2$ adsorption characteristics were examined. The results showed that with the increase in activation temperature from 800 to $900^{\circ}C$, the total pore volume and specific surface area sharply increased from 1.2165 to $1.2500cm^3/g$ and 1281 to $1526m^2/g$, respectively. However, the values for both these parameters decreased at temperatures above $1000^{\circ}C$. The best $CO_2$ adsorption capacity of 10.9 wt % was obtained for the CA-K-900 sample at 298 K and 1 bar. This result highlights the importance of the structural and textural characteristics of the carbon aerogel, prepared at different activation temperatures on $CO_2$ adsorption behaviors.