• Journal of Korean Society for Atmospheric Environment
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• v.14 no.2
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• pp.133-142
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• 1998

Gas adsorption on adsorbents depends on temperatures and pressures. When these parameters are fixed, the adsorption capability and selectivity can not be changed. If the gas adsorption is controlled by another factor like electromagnetic field, the adsorption and desorption can be managed by much intentional way. The microwave has characteristics to excite particular components such as water without destroying it. In this study, microwave was irradiated to the adsorbent of an NaY zeolite which is almost transparent to microwave. As vapor of 1, 1, 2- trichloro-1, 2, 2-trifluoroethane (CFC-113) and water flowed simultaneously on the zeolite packed in a column at room temperature, only water was adsorbed. The . adsorbed water was removed from the zeolite and then replaced by CFC-113, since the microwave was irradiated. Greater the power of microwave was, more CFC-113 was adsorbed. The water adsorption took place again after a latent period by stopping the microwave irradiation.

• Journal of the Korean Applied Science and Technology
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• v.27 no.1
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• pp.56-60
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• 2010

Titanium dioxide particles are used as photocatalysts, sensors, adsorbents and catalyst. Core-shell polymers of inorganic/organic pair, which have both core and shell component, were synthesized by sequential emulsion polymerization using Acrylate as a shell monomer and potassium persulfate (KPS) as an initiator. We found that when Acrylate core prepared by adding 0.5~2.0 wt% EU-S133D, Titanium dioxide / Acrylate core-shell polymerization was carried out on the surface of Titanium dioxide particle without forming the new Titanium dioxide particle during acrylate shell polymerized in the inorganic/organic core-shell polymer preparation. The structure of core-shell polymer were investigated by measuring to the thermal decomposition of polymer composite using thermogravimetric analyzer(TGA) and morphology of latex by scanning electron microscope(SEM).

• Korean Chemical Engineering Research
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• v.53 no.6
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• pp.770-775
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• 2015

Adsorption of Congo Red (CR) from dye-containing effluents using modified bentonite (MB) has been investigated here. Isothermal studies were conducted to ascertain maximum adsorption capacity of the adsorbent. MB exhibited superior adsorption capacity compared to other low-cost adsorbents. Experimental data fitted the Langmuir isotherm better, indicating monolayer coverage of CR on MB. The feasibility of the process was measured in terms of separation factor $R_L$. The values of Gibbs free energy, entropy and enthalpy were calculated from the thermodynamics of the process. Adsorption was feasible and spontaneous, being endothermic. Analytical techniques including SEM, EDS, FTIR and XRD were applied to characterize MB and also to provide conclusive proof of the accumulation of CR on to MB.

• YAKHAK HOEJI
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• v.23 no.3_4
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• pp.133-140
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• 1979

The adsorption of erythrosine in the aliphatic alcohols by antibiotics such as ampicillin anhydrous, ampicillin trihydrate, amoxicillin trihydrate, cephalexin monohydrate was studied. The adsorption isotherms were all described with Freudlich equation. From the various experimerts, it was found that the adsorption of erythrosine by antibiotics in the aliphatic alcohols was affected by the solubility of adsorbents. The adsoption in the mixture of aliphatic alcohols and water is related with the dielectric constant of mixed solvents. According to increase in the pH values of aqueous solution, the adsorption of erythrosine for antibiotics is decreased, but increased in the mixture of aliphatic alcohols and water. The adsorption of erythrosine in the suspension of antibiotics showed a correlation with the temperature. Colloidal silica which is used as stabilizer had a favorable effect on the adsorption of erythrosine in the suspension of antibiotics.

• Ceramist
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• v.22 no.3
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• pp.243-255
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• 2019

Graphene, a two-dimensional material with a single atomic layer, has recently become a major research focus in various applications such as electronic devices, sensors, energy storage, catalysts, and adsorbents, because of its large theoretical surface area, excellent electrical conductivity, outstanding chemical stability, and good mechanical properties. Recently, 3D nanoporous graphene structures have received tremendous attention to expand the application of 2D graphene. Here, we overview the synthesis of 3D nanoporous graphene network structure with two-dimensional graphite oxide sheets, the control of porous parameters such as specific surface area, pore volume and pore size etc, and the modification of electronic structure by heteroatom doping along with its various applications. The 3D nanoporous graphene shows superior performance in diverse applications as a promising key material. Consequently, 3D nanoporous graphene can lead the future for advanced nanotechnology.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.11
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• pp.929-934
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• 2011

The adsorption kinetic study of ruthenium complex, N3, onto nanoporous titanium dioxide ($TiO_2$) photoanodes has been carried out by measuring dye uptake in-situ. Three simplified kinetic models including a pseudo first-order equation, pseudo second-order equation and intraparticle diffusion equation were chosen to follow the adsorption process. Kinetic parameters, rate constant, equilibrium adsorption capacities and related coefficient coefficients for each kinetic model were calculated and discussed. It was shown that the adsorption kinetics of N3 dye molecules onto porous $TiO_2$ obeys pseudo second-order kinetics with chemisorption being the rate determining step. Additionally the heterogeneous surface and the pore size distribution of porous $TiO_2$ adsorbents were also discussed.

• Archives of Pharmacal Research
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• v.14 no.3
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• pp.249-254
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• 1991

Activated carbons from rice-straw can be used as an adsorbents for the purification of water were prepared and evaluated. The adsorptive capacities of activated carbons were measured by iodine, potassium permangante, phenol and metals. It was observed by electron microscope (SEM) and IR spectrum that organic components in the rice-straw and its carbonization product were disappeared. Slit-shaped and porousstructures were formed by activation. There was no relationship between temperature and adsorption of iodine but adsorption of potassium permanganate increased as temperature rose. The adsorption of the phenol was greater than 99%. The adsorption data of phenol at $25^\circ{C}$ obeyed the Freundlich's isotherm. Various metals except sodium were not removed by activated carbon.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.12 no.sup1
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• pp.93-97
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• 2009

Worldwide, diarrhea remains one of the most common illnesses among children. Oral rehydration therapy (ORT) is the cornerstone of diarrhea treatment. Yet, the rates at which ORT is used are still disappointingly low. Additional treatment interventions include antimotility drugs, antisecretary drugs, adsorbents, probiotics, antibiotics, oral immunoglobulin, micronutrient supplementation. Drugs are generally not necessary. However, selected probiotics may reduce the duration and intensity of diarrhea. Zinc is beneficial especially to malnourished children with diarrhea. Antibiotic treatment is effective mainly in shigella and cholera infection. Other drugs may be effective but require further investigations.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.123-127
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• 2003

Changes in pyrene partitioning due to mineral surface adsorptive fractionation processes of humic substances (HS) were examined in model environmental systems. For purified Aldrich humic acid(PAHA), carbon-normalized pyrene binding coefficients ( $K_{oc}$ ) for the residual (i.e., nonadsorbed and dissolved) PAHA components were different from the original dissolved PAHA $K_{oc}$ , value prior to contact with mineral suspensions. A positive correlation between the extent of pyrene binding and weight-average molecular weight (M $W_{w}$) of residual PAHA components was observed, which appeared to be unaffected by the specific mineral adsorbents use and fractionation mechanisms. A similar positive correlation was not observed with the adsorbed PAHA components, suggesting that conformational changes occurred for the mineral-associated components upon adsorption. Nonlinear pyrene sorption to mineral-associated PAHA was observed, and the degree of nonlinearity is hypothesized to be dependent on adsorptive fractionation effects and/or structural rearrangement of the adsorbed PAHA components.s.

• Journal of Environmental Science International
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• v.21 no.5
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• pp.573-578
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• 2012

In this study, adsorption of polychlorinated biphenyls(PCBs) in transformer oil on powder activated carbon (PAC) and synthetic zeolite was evaluated. Adsorption characteristics of PCBs on the PAC and zeolite has been investigated in a batch system with respect to adsorbents amount and contact time. BET results showed 908 m2/g for PAC and 483 m2/g for zeolite. The adsorption capacity of PCBs increased with an increasing input amount of absorbent. The adsorption experimental results showed that PAC removed 90% of input PCBs in transformer oil while zeolite removed only 64%. Adsorption of PCBs to PAC and zeolite fit the Freundlich model well. The Freundlich parameter, Kf, for PAC and zeolite was 193.1 and 43.0 respectively, indicating that PAC is effect adsorbent for PCBs adsorption in transformer oil.