• Journal of Radiation Protection and Research
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• v.8 no.1
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• pp.15-25
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• 1983

The sequential separation of Ru-103, Cs-137 and Ce-144 was carried out by organic cation exchanger, Amberite CG-120, and inorganic ion exchangers, silica gel and montmorillonite. The optimum conditions of Ru-103, Cs-137 and Ce-144 on Amberite CG-120 are 0.01M-, 0.01M- and 0.1IM- hydrochloric acid for the adsorption, and 3M-, 3M- and 5M-hydrochloric acid for the desorption, respectively. The optimum conditions of Ru-103, Cs-137 and Ce-144 on silica gel are pH 8, pH 8 and pH 8 for the adsorption. and 3M-, 1M- and 1M-hydrochloric acid for the desorption. respectively. The optimum conditions of Ru-103, Cs-137 and Ce-144 on montmorillonite are pH 8, 0.01M-hydrochloric acid and pH 4 for the adsorption, and 1M-, 5M- and 3M-hydrochloric acid for the desorption. respectively. The adsorption which occurs at lower ionic strength and the differences in desorption ionic strength are utilized for the separation of tracer mixture in continuous experiments. The individual separation of Ru-103, Cs-137 and Ce-144 can be carried out more efficiently with montmorillonite than with silica gel and Amberite CG-120.

• Journal of Environmental Science International
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• v.21 no.7
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• pp.787-795
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• 2012

The purpose of this study is to synthesize transition metal doped mesoporous silica catalyst and to characterize its surface in an attempt to decomposition of $N_2O$. Transition metal used to surface modification were Ru, Pd, Cu and Fe concentration was adjusted to 0.05 M. The prepared mesoporous silica catalysts were characterized by X-ray diffraction, BET surface area, BJH pore size, Scanning Electron Microscopy and X-ray fluorescence. The results of XRD for mesoporous silica catalysts showed typical the hexagonal pore system. BET results showed the mesoporous silica catalysts to have a surface area of 537~973 $m^2/g$ and pore size of 2~4 nm. The well-dispersed particle of mesoporous silica catalysts were observed by SEM, the presence and quantity of transition metal loading to mesoporous surface were detected by XRF. The $N_2O$ decomposition efficiency on mesoporous silica catalysts were as follow: Ru>Pd>Cu>Fe. The results suggest that transition metal doped mesoporous silica is effective catalyst for decomposition of $N_2O$.

• Bulletin of the Korean Chemical Society
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• v.28 no.4
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• pp.529-532
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• 2007

Combined temperature programmed reaction (TPR) and infrared (IR) spectroscopic studies for Fischer- Tropsch reaction have been performed over Ru/SiO2 and Ru-Ag/SiO2 supported catalysts. Reaction of linearly absorbed CO with hydrogen starts at 375 K over Ru/SiO2 catalyst and reaches maximum at 420 K accompanied with an intensity decrease of linear CO absorption. The reaction with bridged absorbed CO peaks around 510-535 K. Addition of Ag yields mixed Ru-Ag bimetallic sites while it suppresses the formation of bridged bonded CO. Formation of methane on this modified surface occurs at 390 K and reaches maximum at 444 K. Suppression of hydrogen on the Ag-doped surface also occurs resulting in the formation of unsaturated hydrocarbons and of CHx intermediates not observed with Ru/SiO2 catalyst. Such intermediates are believed to be the building blocks of higher hydrocarbons during the Fischer-Tropsch synthesis. Linearly absorbed CO is found to be more reactive as compared to bridged CO. The Ag-modified surface also produces CO2 and carbon. On this surface, hydrogenation of CO begins at 390 K and reaches maximum at 494 K. The high temperature for hydrogenation of absorbed CO and C over Ru-Ag/SiO2 catalyst as compared to Ru/SiO2 catalyst is due to the formation of Ru-Ag bimetallic surfaces impeding hydrogen adsorption.

• Korean Chemical Engineering Research
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• v.46 no.4
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• pp.752-755
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• 2008

Mesoporous SBA-15 silica-supported TsCHDA and TsDPEN ligands have been prepared by reaction of SBA-15 silica with (1R,2R)-N-(trimethoxysilylpropyl-N-sulfonyl)-1,2-cyclohaxanediamine or (1R,2R)-N-(trimethoxysilylpropyl-N-sulfonyl)-1,2-diphenylethylenediamine-1,2-diphenylethylenediamine, respectively. The Ru complexes exhibited excellent catalytic activity and satisfactory enantioselectivity in the asymmetric hydrogen transfer of ketones under microwave conditions. The heterogeneous Ru catalyst was reusable as well as air-stable to allow easy use. Microwave-assisted efficient procedure has been developed for asymmetric hydrogen transfer.

• Applied Chemistry for Engineering
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• v.21 no.1
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• pp.81-86
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• 2010

On adsorbing carbon monoxide (CO) on the silica supported ruthenium/iron alloy ($Ru/Fe-SiO_2$) samples above mole ratio 9/1 of Ru/Fe five bands ($2138.7{\sim}2142.5cm^{-1}$, $2067.3{\sim}2073.1cm^{-1}$, $1976.7{\sim}2017.2cm^{-1}$, $1737.9{\sim}1799.3cm^{-1}$, $1625.7cm^{-1}$) were observed, and in $Ru/Fe-SiO_2$ samples below mole ratio 8/2 of Ru/Fe two bands ($1934.0{\sim}1990.2cm^{-1}$, $1625.7cm^{-1}$) were observed. The $2138.7{\sim}2142.5cm^{-1}$ bands, the $2067.3{\sim}2073.1cm^{-1}$ bands, and the $1988.3{\sim}2030.7cm^{-1}$ bands may be ascribed to stretching vibrations of CO molecules lineally bonded to the Ru atoms on supported Ru/Fe cluster surface, the $1737.9{\sim}1799.3cm^{-1}$ bands to stretching vibrations of CO molecules bridge bonded to the Ru atoms on supported Ru/Fe cluster surface or to stretching vibrations of CO molecules bonded to the Ru atoms on high Miller index planes, and the $1934.0{\sim}1990.2cm^{-1}$ bands to stretching vibrations of CO molecules lineally bonded to the Fe atoms on supported Ru/Fe cluster surface. The absorbances of the $1934.0{\sim}1990.2cm^{-1}$ bands in $Ru/Fe-SiO_2$ samples gradually increased with the increases of Ru/Fe mole ratio below the ratio of 8/2. This phenomena may be ascribed to the increases of Fe concentration of surface compared with the one of the sample and to the increases of surface area of supported Ru/Fe cluster according as increase of Ru/Fe mole ratio below the ratio of 8/2 compared with the $Fe-SiO_2$ sample.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.94.1-94.1
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• 2011

In this work, ordered mesoporous carbons (OMCs) were prepared by the conventional templating method using mesoporous silica (SBA-15) for Pt-Ru catalyst supports in fuel cells. The influence of surface modification on carbon supports on the electrochemical activities of Pt-Ru/OMCs was investigated with different pH. The neutral-treated OMCs (N-OMCs), base-treated OMCs (B-OMCs), and acid-treated OMCs (A-OMCs) were prepared by treating OMCs with 2 M $C_6H_6$, 2 M KOH, and 2 M $H_3PO_4$, respectively. The surface characteristic of the carbon supports were determined X-ray photoelectron spectroscopy (XPS). The electrochemical activities of the Pt-Ru catalysts had been enhanced when the OMCs supports were treated by basic or neutral agents, while the electrochemical activities had been decayed for the A-OMCs supported Pt-Ru.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.652-655
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• 2009

The bimodal porous carbons were synthesized by using imprinting method with templates of SBA-15 particle and silica sphere and applied as supporting materials for the electro-catalyst of polymer electrolyte fuel cell (PEFC). The silica spheres with diameter size of 100 nm and SBA-15 particle having 200 nm -250 nm diameter and 700 nm -900 nm length were synthesized in this work. The bimodal porous carbons (S100) were prepared by using the silica spheres and SBA-15 as templates and mesophase pitch as a carbon source. The PtRu nanoparticle of ca. 1.9 nm were supported on the bimodal porous carbon support and the resulting PtRu/S100 catalysts was tested by the cyclic voltammetry. The use of bimodal porous carbon showed in comparable electro-catalytic activities with commercial catalyst. Though unclear effects of bimodal porosity of supports could be obtained in the scope of this study, morphological advantage in electrical conductivity can be considered on the electro-catalytic activity.

• Applied Chemistry for Engineering
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• v.17 no.4
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• pp.349-356
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• 2006

We have investigated adsorption and desorption properties of CO adsorption on silica supported Ru/Ni alloys at various Ru/Ni mole content ratio as well as CO partial pressures using Fourier transform infrared spectrometer (FT-IR). For Ru-$SiO_{2}$ sample, four bands were observed at $2080.0cm^{-1}$, $2021.0{\sim}2030.7cm^{-1}$, $1778.9{\sim}1799.3cm^{-1}$, $1623.8cm^{-1}$ on adsorption and three bands were observed at $2138.7cm^{-1}$, $2069.3cm^{-1}$, $1988.3{\sim}2030.7cm^{-1}$ on vacumn desorption. For Ni-$SiO_{2}$ sample, four bands were observed at $2057.7cm^{-1}$, $2019.1{\sim}2040.3cm^{-1}$, $1862.9{\sim}1868.7cm^{-1}$, $1625.7cm^{-1}$ on adsorption and two bands were observed at $2009.5{\sim}2040.3cm^{-1}$, $1828.4{\sim}1868.7cm^{-1}$ on vacumn desorption. These absorption bands correspond with those of the previous reports approximately. For Ru/Ni(9/1, 8/2, 7/3, 6/4, 5/5; mole content ratio)-$SiO_{2}$ samples, three bands were observed at $2001.8{\sim}2057.7cm^{-1}$, $1812.8{\sim}1926.5cm^{-1}$, $1623.8{\sim}1625.7cm^{-1}$ on adsorption and three bands were observed at $2140.6cm^{-1}$, $2073.1cm^{-1}$, $1969.0{\sim}2057.7cm^{-1}$ on vacumn desorption. The spectrum pattern observed for Ru/Ni-$SiO_{2}$ sample at 9/1 Ru/Ni mole content ratio on CO adsorption and on vacumn desorption is almost like the spectrum pattern observed for Ru-$SiO_{2}$ sample. But the spectrum patterns observed for Ru/Ni-$SiO_{2}$ samples under 8/2 Ru/Ni mole content ratio on CO adsorption and vacumn desorption are almost like the pattern observed for $Ni-SiO_{2}$ sample. It may be suggested surfaces of alloy clusters on the Ru/Ni-$SiO_{2}$ samples contain more Ni components than the mole content ratio of the sample considering the above phenomena. With Ru/Ni-$SiO_{2}$ samples the absorption band shifts may be ascribed to variations of surface concentration, strain variation due to atomic size difference, variation of bonding energy and electronic densities, and changes of surface geometries according to surface concentration variation. Studies for CO adsorption on Ru/Ni alloy cluster surface by LEED and Auger spectroscopy, interation between Ru/Ni alloy cluster and $SiO_{2}$, and MO calculation for the system would be needed to look into the phenomena.

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2765-2770
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• 2011

Organic dye-doped glasses, viz., ruthenium (II) tris(4,7'-diphenyl-1,10'-phenanthroline) $[Ru(dpp)_3]^{2+}$ incorporated into thin silica xerogel films produced by the sol-gel method, were prepared and their $O_2$ quenching properties investigated as a function of the $[Ru(dpp)_3]^{2+}$ concentration (3-400 ${\mu}M$) within the xerogel. The ratio of the luminescence from the $[Ru(dpp)_3]^{2+}$-doped films in the presence of $N_2$ and $O_2$ ($I_{N2}/I_{O2}$) was used to describe the film sensitivity to $O_2$ quenching. ($I_{N2}/I_{O2}$ changed three-fold over the $[Ru(dpp)_3]^{2+}$ concentration range. Time-resolved intensity decay studies showed that there are two discrete $[Ru(dpp)_3]^{2+}$ populations within the xerogels (${\tau}_1$ ~ 300 ns; ${\tau}_2$ ~ 3000 ns) whose relative fraction changes as the $[Ru(dpp)_3]^{2+}$ concentration changes. The increased $O_2$ sensitivity that is observed at the higher $[Ru(dpp)_3]^{2+}$ concentrations is a manifestation of a greater fraction of the 3000 ns $[Ru(dpp)_3]^{2+}$ species (more susceptible to $O_2$ quenching). A model is presented to describe the observed response characteristics resulting from $[Ru(dpp)_3]^{2+}$ distribution within the xerogel.

• Applied Chemistry for Engineering
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• v.17 no.2
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• pp.223-228
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• 2006

Pore-size controlled porous carbons for the catalyst supports of the direct methanol fuel cell were prepared from the mesophase pitch by using the silica spheres with different sizes. Pitch solution in THF and spheres were mixed, carbonized and etched by 5 M NaOH to make porous carbon. Specific surface area of the porous carbons was $14.7{\sim}87.7m^2/g$ and average pore diameter was 50~550 nm which were dependent on the size of silica spheres. Aqueous reduction method was used to load 60 wt% PtRu on the prepared porous carbon supports. The electro-oxidation activity of the supported 60 wt% Pt-Ru catalysts was measured by cyclic voltammetry and unit cell test. For the 60 wt% Pt-Ru/porous carbon synthesized by 50 nm silica, current density value in the cyclic voltammetry test was $123mA/cm^2$ at 0.4 V and peak power density in the unit cell test were 105 and $162mW/cm^2$ under oxygen at 60 and $80^{\circ}C$, respectively.