• Journal of Soil and Groundwater Environment
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• v.7 no.4
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• pp.24-30
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• 2002

The laboratory adsorption batch tests were performed to investigate the adsorption characteristics of Pb on kaolinite. The characteristics such as adsorption equilibrium time, adsorption capacity, adsorption isotherm were studied, and also the effects of pH and the mixing ratio on the adsorption of Pb on kaolinite were investigated. Test results show that the adsorption equilibrium state was reached within 24 hours, and the adsorbed amount of Pb increased, but the adsorption efficiency over the initial concentration of 198 mg/l decreased, with increasing the initial concentration of Pb. And the adsorption constant, 1/n was obtained 0.9584 by Freundlich isotherm equation. Regardless of the initial concentration of Pb. the adsorbed amount of Pb as well as the adsorption efficiency were increased with increasing pH values and converged to a certain constant value above 8 of pH values. And also the adsorbed amount of Pb increased with the mixing ratio, but its efficiency increased with the mixing ratio up to 8 and then showed the decreasing tendency above that.

• Journal of the Korean Society of Tobacco Science
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• v.35 no.1
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• pp.7-12
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• 2013

A Solid-phase micro extraction(SPME) was evaluated as a tool for headspace sampling of tobacco samples. Several experimental parameters (sampling temperature, pH, and type of SPME fibers) were optimized to improve sampling efficiency in two aspects ; maximum adsorption and selective adsorption of volatile organic acids onto SPME fibers. Among four types of SPME fibers such as PDMS(Polydimethylsiloxane), PA(Polyacrylate), Car/PDMS (Carboxen/Polydimethylsiioxane) and PDMS/DVB(Polydimethylsiioxane/Divinylbenzene) which were investigated to determine the selectivity and adsorption efficiency. A variety of tobacco samples such as flue cured, burley and oriental were used in this study. The effect of these parameters was often dominated by the physical and chemical nature (volatility, polarity) of target compounds. This method allowed us to make important improvements in selectivity and sensitivity. The Car/PDMS fiber was shown to be the most efficient at extracting the 10 selected volatile organic acids. The parameters were optimized: $80^{\circ}C$ adsorption temperature, 30 min of adsorption time, $240^{\circ}C$ desorption temperature, 1 min of adsorption time.

• Journal of the Korean Geosynthetics Society
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• v.10 no.1
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• pp.53-61
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• 2011

This study was conducted to confirm the adsorption capacity of CFW(Carbonized Foods Waste), which is produced by the process of recycling waste, in PRB method that Electrokinetic(E/K) method was applied. The batch test was carried out to analyze the adsorption characteristics of CFW for adsorbing the organic compounds. The organic compounds used in the batch test were Phenanthrene and Trichloroethylene(TCE), and the anionic surfactant(SDS) and the nonionic surfactant(Brij$^{(R)}$30) were used for the surfactants. The results of the batch test confirmed that the adsorption efficiency of Phenanthrene was 99% and TCE was 26%. The each compounds compared with the adsorption isotherms, which is calculated by the Langmuir and Freundlich models. The results indicated that Phenanthrene is fitted to the linear Langmuir model, whereas the distribution of TCE is unclear. The results of the batch test used in surfactants confirmed that the adsorption efficiency of CFW using Phenanthrene was reduced to 6~8%. However, the adsorption efficiency of CFW in TCE was increased up to 81% by surfactants. Especially, the nonionic surfactant was excellent in the adsorption of CFW using TCE. Nevertheless, the adsorption efficiency of CFW in Phenanthrene was still higher than TCE. Therefore, the adsorption efficiency of CFW in Phenanthrene was better than in TCE. In PRB method using E/K method, the adsorption of CFW used nonionic surfactant is better to use than the anion surfactants on the organic compounds.

• Journal of Wellbeing Management and Applied Psychology
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• v.6 no.1
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• pp.17-22
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• 2023

Purpose: VOCs (volatile organic compounds) are all the organic compounds that react with solar rays and increase the concentration of ozone in the troposphere and are partially also known as carcinogens. The adsorption using activated carbon is usually applied to remove VOCs. Research design, data and methodology: The 20 places of surface coating facilities were selected to evaluate the emission amount of VOCs in Seoul. In addition, the removal efficiency of VOCs in 25 places of automobile coating facilities was evaluated. Results: The average emission amount of VOCs was 10.903 kg/hr from automobile coating facilities, while 3.520 kg/hr from other surface coating facilities. The removal efficiency in adsorption with the combustion catalytic process has the mean value of 87.9% and the regeneration efficiency of activated carbon has the mean value of 95.0%. Conclusions: The removal efficiency in adsorption with the biofiltration process has the mean value of 89.8% and the regeneration efficiency of activated carbon has the mean value of 94.8%. The removal efficiency in the plasma catalyst process has the mean value of 79.3%.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.20 no.3
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• pp.153-157
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• 2010

We studied the adsorption efficiency of steelmaking slag in removing volatile organic compounds (VOCs) for increasing the recycling rate of steel-making slag. Ceramic filter was prepared by mixing the steel-making slag and the diatomite which is used as adsorbents due to the advantage of the high specific surface area and regular mesopores. The adsorption efficiency for VOCs removal was about 80%, 96% and 85% in acetaldehyde, formaldehyde and ammonia, respectively. The adsorption efficiency over 80% for all The gases showed the practical possibility as the adsorption filter.

• Journal of the Korean Applied Science and Technology
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• v.27 no.3
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• pp.318-324
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• 2010

In this study, commercial pellet type sorbents for the collection of $CO_2$ from a local municipal waste incinerator were prepared and characterized in terms of adsorption efficiency by varying the operating conditions of a field process. The concentration of $CO_2$ in the flue gas ranged from 8 to 10%, which entered the test packed bed. As a result of this experiment, the sorbent procured from A-company, which is mainly composed of calcium compounds, showed the highest adsorption efficiency. The regeneration efficiency was fairly low, however. It also was found that based on adsorption breakthrough time, the relatively low flow rate of 10 LPM into the bed allowed higher collection efficiency. The higher flow rate of 40 LPM, on the other hand, tended to decrease the retention of the adsorption.

• Korean Journal of Environmental Agriculture
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• v.26 no.4
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• pp.286-296
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• 2007

To increase phosphate (P) availability in soils, the efficiency of silicate (Si) in reducing P adsorption was investigated by competitive adsorption tests under changing conditions of pH, ion concentrations, and order of anion addition along with single adsorption properties of each ion at $20^{\circ}C$. In the single ion adsorption study, P and Si ions showed the opposite reaction patterns: phosphate adsorption decreased with increasing pH and attained adsorption maximum however, silicate adsorption increased with increasing pH without attaining adsorption maximum. Phosphorus and Si adsorption were influenced by pH in the range of 5.0 - 9.0 and the type and amount of P and Si concentration. Silicate added to soil before P or in a mixture with P significantly reduced P adsorption above pH 7.0; however, there was no significant Si-induced decreased in P adsorption at pH 5.0 when anions were added as mixture. The efficiency of Si in reducing P adsorption increased with increasing Si concentration and pH. The effect of P on Si adsorption was relatively small at pH 5.0 and no effect of P on silicate adsorption was observed at pH 9.0. The presence of Si strongly depressed P adsorption when Si was added before P compared to P and Si added as a mixture. These results suggest that application of Si may decrease P adsorption and increase the availability of P in soils. Furthermore, a Si source would be better to add before P application to enhance the availability of P in soils.

• Clean Technology
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• v.27 no.2
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• pp.160-167
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• 2021

This study investigated the environmental effects of improving the general-type activated carbon adsorption tower used at the Sihwa/Banwol Industrial Complex with use of a cartridge-type activated carbon adsorption tower for the application of an activated carbon co-regenerated system. Four general-type activated carbon adsorption towers and two cartridge-type activated carbon adsorption towers were selected to analyze the properties of activated carbon and to compare the efficiency of reducing environmental pollutants. The results showed that the activated carbon used in the cartridge-type activated carbon adsorption towers was high quality activated carbon with an iodine adsorption force of more than 800 mg/g and that a good adsorption performance was maintained within the replacement cycle. From an analysis of the environmental pollutant reduction efficiency, it was confirmed that the cartridge-type activated carbon adsorption tower functioned properly as a prevention facility for handling emissions pollutants with a treatment efficiency of total hydrocarbons (THC), toluene, and methylethylketone (MEK) components of 71%, 77%, and 80%, respectively. The general activated carbon adsorption tower, which was confirmed to use low-performance activated carbon, had a very low treatment efficiency and did not function properly as a prevention facility for dealing with emission pollutants. It is believed that it is possible to reduce pollutants during operations by changing from the general-type activated carbon adsorption tower to a cartridge-type activated carbon adsorption tower.

• Journal of Environmental Science International
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• v.5 no.2
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• pp.195-201
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• 1996

This study was conducted for the efficient utilization of a scoria, which is abundantly found in Cheju island, as adsorbent and the scoria was examined for its performance in clarification of adsorption of heavy metal ions. The order in heavy metal ions adsorbed on scoria was; Pb+>Cd^{2+}$>Cu^{2+}$>Ag^+$>Co^{2+}$>Zn^{2+}$>Cr^{3+}$>Cr^{6+}$. This tendency was relatively consistent with the decreasing order of radius of hydrated metal ion. Also, the smaller scoria size and the larger amounts of scoria showed higher removal efficiency for heavy metal ions. The same scoria size showed more effective removal efficiency for heavy metal ions at lower initial concentration than at higher initial concentration. The adsorption abilities of original scoria and chemically treated scoria were compared. Adsorption isotherm of scoria was generally obeyed to Freundlich formula than langmuir formula and Freundlich constant, than was obtained in the range of 0.2~0.4.

• Corrosion Science and Technology
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• v.5 no.5
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• pp.160-167
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• 2006

S-Acetyl Isothiourea Acetate (S-AITA) was synthesized in the laboratory and this influence on the inhibition of corrosion of mild steel in 1.11 N hydrochloric and 1.12 N sulphuric acids was investigated by weight loss and potentiostatic polarization techniques at 303K, 353K and 403K. These results were confirmed by the impedance technique. The inhibition efficiency increased with increase in concentration of inhibitor and decreased with rise in temperature from 303K to 403K. The maximum inhibition efficiency of S-AITA was found to be 99.95% (0.5% of S-AITA) at 303K in sulphuric acid. The adsorption of this compound on the mild steel surface from the acids has been found to obey Temkin's adsorption isotherm. The potentiostatic polarization results revealed that S-AITA was a mixed type inhibitor. Some thermodynamic parameters i.e., activation energy (Ea), free energy of adsorption (${\Delta}G_{ads}$), enthalpy of adsorption (${\Delta}H$) and entropy of adsorption (${\Delta}S$) were also calculated from weight loss data.