• Applied Chemistry for Engineering
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• v.23 no.4
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• pp.383-387
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• 2012

This paper presents an easy way to prepare carbon dioxide sorbent by using commercially available fumed silica particles (AEROSIL). AEROSIL was impregnated with various concentration of polyethyleneimine (PEI) in methanol and $CO_2$ capture ability was analyzed by thermo gravity analysis (TGA). The $CO_2$ adsorption capacity of 50 wt% PEI-impregnated AEROSIL was 126.2 mg/g-sorbent at $75^{\circ}C$ and this capacity was substantially higher than that of the mesoporous silica such as HMS (101.0 mg/g-sorbent) and MSU-J (66.1 mg/g-sorbent).

• Clean Technology
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• v.16 no.2
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• pp.95-102
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• 2010

Sulfonic acid (-SO3H) functionalized mesoporous silica containing HMS, SBA 15(S15), MCM 41(M41) were synthesized by post-synthesis and co-condensation method. Their catalytic performance is tested by dehydration reaction of D-xylose to furfural. As a result, good conversion and selectivity was obtained using water as an environmentally friendly solvent. Additionally, increased amounts of sulfuric acid in catalysts resulted in improved conversion of D-xylose. All of the acid-functionalized mesoporous silica showed higher selectivity than other solid acids such as ${\gamma}-Al_{2}O_{3}$ and zeolite.

• Bulletin of the Korean Chemical Society
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• v.26 no.9
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• pp.1381-1384
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• 2005

Surface modification of tridimensional cubic mesoporous silica, SBA-16, was investigated with pendant arm functionalized cobalt diaminosarcophagine (diAMsar) cage complex which covalently grafted onto the silica surface through the silication with sylanol group. The spectroscopic results showed that the mesoporous structure was preserved under the $[Co(diAMsar)]^{3+}$ grafting reaction condition. Successful grafting prevented the cobalt diAMsar cage from leaching out from the SBA-16 support.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.5
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• pp.719-724
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• 2011

The excessive phosphate in water causes eutrophication which destroys water environment. In this study, mesoporous silica was synthesized and several functional groups were attached on it. Samples were tested to identify the ability to remove phosphate. The structures of synthesized materials were analyzed by X-ray diffractions (XRD), Fourier transform-infrared (FT-IR) and surface area analysis, Brunauer-Emmett-Teller (BET). To determine the maximum phosphate adsorption capacities and sorption rate, the equilibrium test and kinetic test was conducted. Among functionalized SBA-15 samples, pure SBA-15 didn't adsorb phosphate but Al-SBA-15 and Ti-SBA-15 showed good performances to remove phosphate. The maximum phosphate adsorption capacity of Al-SBA-15 was efficient compared to other adsorbents.

• Journal of Adhesion and Interface
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• v.15 no.2
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• pp.63-68
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• 2014

Hollow mesoporous carbon nitride material with sphere shape was synthesized using polystyrene sphere as template and cyanamide as nitrogen and carbon atom sources via thermal treatment process. The process of the silica removal is not necessary because silica as template is not in use for the synthesis of hollow mesoporous carbon nitride material and any solvents are also not in use. The size of polystyrene spheres was about 170 nm. Hollow diameter and wall thickness were 82 nm and 13 nm, respectively, in hollow mesoporous carbon nitride sphere. Surface area, mesopore size and pore volume of hollow mesoporous carbon nitride material was $188m^2g^{-1}$, 3.8 nm and $0.35cm^3g^{-1}$, respectively. The wall in hollow sphere has graphitic structure. Hollow mesoporous carbon nitride material has potential applications in the area of fuel cell, catalysis, photocatalysis, electroemmision device, etc.

• Bulletin of the Korean Chemical Society
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• v.27 no.6
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• pp.808-816
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• 2006

Among the many forms of mesoporous materials, thin films are important for the potential applications of this class of materials. Compared with the powder forms, however, there has been relatively little work done on thin films probably because of the lack of suitable and generalized synthetic mechanisms established. In this account, we will review the issues on mesoporous thin films with emphasis on the necessity of forming films with accessible pores from the film surfaces and on mesoporous thin films with metal oxides other than silica. Various methods that have been tried to utilize mesoporous thin films with accessible pores as templates for the synthesis of nanostructured materials are reviewed with the emphasis on the advantages of the electrochemical deposition technique.

• Journal of Electrochemical Science and Technology
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• v.5 no.2
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• pp.58-64
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• 2014

The surface of an ordered mesoporous silica (OMS) was functionalized using 1H,1H,2H,2H-perfluorooctyltrimethoxysilane at $20^{\circ}C$ and $60^{\circ}C$. It was shown that only elevated temperature allows lyophobic properties on the walls of OMS, eventually preventing pore flooding with nonaqueous electrolytes. The functionalized OMSs (OMS-F) were characterized with various techniques: wettability test, $N_2$ sorption measurement, high-resolution transmission electron microscopy (HR-TEM). Cathodes of $10mg/cm^2$ loading were prepared with a commercial Pt/C catalyst and polyvinylidene fluoride (PVDF, 2.5 wt.%) binder using a typical doctor blade method on a commercial gas diffusion layer (GDL) in the presence or in the absence of OMS-F additives. Subsequent discharge-charge curves were taken in a 1M LiTFSI-TEGDME electrolyte at 60oC in pure oxygen atmosphere. It was found that the discharge capacity was significantly affected by OMS-F: 5 wt.% of additive extended discharge capacity by a factor 1.5. On the other hand, a similar OMS material but synthesized at $20^{\circ}C$ did not show lyophobic properties and deteriorated cathode capacity.

• KSBB Journal
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• v.28 no.3
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• pp.208-212
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• 2013

Four types of mesoporous spherical silica adsorbents with different physical properties were prepared by spray pyrolysis and were used for the purification of the anticancer agent paclitaxel from plant cell cultures. Pore size had a greater effect on the removal of plant-derived impurities during the pre-purification of paclitaxel compared with surface area and pore volume. An appropriate pore diameter (~9.07 nm) was required to achieve the highest purity (~46.1%) and yield (~82.3%) of paclitaxel. These results were confirmed by HPLC analysis of the absorbent after treatment and Thermogravimetric analysis of the organic substances bonded to the adsorbent.

• Bulletin of the Korean Chemical Society
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• v.26 no.5
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• pp.709-710
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• 2005

• Environmental Engineering Research
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• v.20 no.4
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• pp.342-346
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• 2015

Haloacetonitriles (HANs) are nitrogenous disinfection by-products (DBPs) that have been reported to have a higher toxicity than the other groups of DBPs. The adsorption process is mostly used to remove HANs in aqueous solutions. Functionalized composite materials tend to be effective adsorbents due to their hydrophobicity and specific adsorptive mechanism. In this study, the removal of dichloroacetonitrile (DCAN) from tap water by adsorption on thiol-functionalized mesoporous composites made from natural rubber (NR) and hexagonal mesoporous silica (HMS-SH) was investigated. Fourier-transform infrared spectroscopy (FTIR) results revealed that the thiol group of NR/HMS was covered with NR molecules. X-ray diffraction (XRD) analysis indicated an expansion of the hexagonal unit cell. Adsorption kinetic and isotherm models were used to determine the adsorption mechanisms and the experiments revealed that NR/HMS-SH had a higher DCAN adsorption capacity than powered activated carbon (PAC). NR/HMS-SH adsorption reached equilibrium after 12 hours and its adsorption kinetics fit well with a pseudo-second-order model. A linear model was found to fit well with the DCAN adsorption isotherm at a low concentration level.