• Journal of the Korea Institute of Building Construction
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• v.17 no.1
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• pp.15-21
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• 2017

WHO reported that millions of people die every year because of diseases induced from environmental pollution. In 2012, approximately 7 million people were killed due to air pollution. Major cause of such pollution includes toxin, chemical waste, radiation and air pollution. Therefore, the significance and interest to indoor air quality has been continuously increased. Especially, the interest in radon, the ARC group 1 carcinogen, is rapidly increasing, and banning the use of construction materials that release radon, repairing aged buildings, and developing ventilators. To reduce the level of radon gas was inflowed to indoors and outdoors, this study is to research and develop a radon gas absorption board using absorbents. The absorbents utilized to absorb the radon gas were porous diatomite, natural zeolite, 4A zeolite and 13X zeolite and employed bentonite and illite, montmorillonites with the property of exchanging anions. As the main binder, magnesium oxide was used, with a content of 25% magnesium chloride.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.1
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• pp.106-110
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• 1998

본 논문에서는 먼저 다층흡착에서 각 흡착층의 결합에너지가 서로 다른 경우의 흡착 등온선을 유도한다. 그리고 유도된 흡착등온식이 저압영역에서 헨리의 실험법칙을 잘 만족시킴을 보인다.

• Journal of the Korean Institute of Gas
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• v.19 no.2
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• pp.37-44
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• 2015

We proposed the improved Langmuir adsorption relations considering volume change effect of coal matrix during primary production of CBM and Enhanced-CBM with injection of carbon dioxide or CCS in coalseam but also volumetric strain. To verify this model, experimental data of pure gas adsorption such as $CO_2$, $CH_4$, and $N_2$ on coals were used to compare conventional Langmuir model with this model. From the results, we obtained that the larger adsorption capacity of coal and the higher adsorption affinity of gas, the larger error occur with Langmuir model. Using this model, however, we found not only substantially better fit in all condition but also reasonable volumetric strain of the coal matrix. We also applied this volume modified pure gas adsorption model to the IAS model to describe gas adsorption and volumetric strain for mixed gas. This modified-IAS model fitting experimental data by Hall et al(1994) improved accuracy of mixed gas adsorption calculation compared with conventional model.

• Korean Journal of Soil Science and Fertilizer
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• v.36 no.4
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• pp.210-217
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• 2003

An alternative method to the empirical approach such as Langmuir and Freundlich model, surface complexation model using thermodynamic database is used to simulate adsorption behavior of cadmium for oxide minerals. Sorption of cadmium onto amorphous silica ($SiO_2$) and synthetic goethite (${\alpha}$-FeOOH) at various conditions of pH, initial cadmium loading, oxide concentration, and ionic strength, were investigated. For both oxide minerals, increasing cadmium concentration resulted in right shifting of the sorption curve of cadmium as the function of pH. The $pH_{50}$, where 50% of cadmium sorbed, of goethite (pH 5.25) was much smaller than that of the silica (pH 7.83). The sorption of cadmium onto both minerals were not affected by the background ion strength from $10^{-1}$ to $10^{-2}$ M of $KNO_3$. It indicated that the binding affinity of goethite surface for cadmium is much stronger than that of silica. The strong affinity of oxide mineral for cadmium can be explained by the existence of coordination or covalent bond between cadmium and surface of it.

• 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.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2004.05a
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• pp.203-206
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• 2004

활성탄 흡착을 통한 도장공정의 건조작업시 발생하는 VOCs 가스중에서 많은 양을 차지하는 톨루엔의 흡착실험의 결과는 아래와 같다. 활성탄을 충전한 고정흡착탑에서 톨루엔의 흡착에 있어서 파과곡선의 파과점은 흡착제의 포화특성에 좌우되며, toluene 가스의 농도, 유량이 증가할수록 감소하였다. 활성탄의 동일한 충전층에 대해 toluene 가스의 유량, 농도가 증가할수록 MTZ와 LUB도 증가함으로 흡착층의 효율이 감소하는 것으로 나타났다.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.05a
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• pp.718-722
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• 1995

공기중에서 천이점 이후까지 산화된 지르칼로이 시편에 LiF, NaF, KF, NnCl, 그리고 LiOH 등을 흡착시켜 산화실험을 수행하였다. NaF, KF, NaCl을 흡착시킨 시편의 산화가 두드러지게 많이 됨을 확인할 수 있었다. LiF, LiOH를 흡착한 시편은 흡착하지 않은 시편과 큰 차이를 보이지 않고 산화가 진행되었다. 이는 Li의 전분이 초기에 산화막을 형성한 fresh 시편과는 달리 충분히 산화가 진행되어서 초기산화막의 존재가 없는 상태에서 흡착되었기 때문에 흡착의 효과가 거의 없는 것으로 나타났다고 사료된다. 이러한 결과를 이용하여 사용 후 핵연료의 보관시 안전성의 문제, 그리고 DUPIC 핵연료의 제작시에 이용될 수 있는 반복적 산화 환원의 방식에 적용될 수 있다.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.7
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• pp.1213-1223
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• 2000

The adsorption characteristics of phenol has been studied by using CDQ (Cokes Drying Quenching) dust as an adsorbent. The adsorption capacity of CDQ dust was shown to be 42% about removal for 300 ppm phenol solution at the equilibrium adsorption time of 60 min. Removal percentage of phenol increased as the initial phenol concentration was raised in the experimental conditions and the adsorption behavior was explained well by Freundlich adsorption isotherm. Kinetic study showed that the adsorption followed 1st, 1.5th, and 2nd-order rate equation in the sequence as the adsorption time passed. Since the adsorption amount of phenol was increased as the adsorption temperature was raised, the adsorption was thought to be endothermic, and several thermodynamic parameters have been calculated based upon experimental data. Adsorbed amount of phenol on CDQ dust changed little according to the variation in the solution pH except for the slight decrease under the strong alkaline condition.

• Journal of the Korean Geotechnical Society
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• v.16 no.4
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• pp.157-170
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• 2000

In this study, we conducted a combined adsorption-sequential extraction analysis(CASA) to investigate temperature effects of single and competitive adsorption of zinc and copper on natural clays. As a result, it was found out that in a single adsorption of zinc, the adsorption was mostly in the exchangeable phase, with increase n temperature. In a competitive adsorption of zinc, this trend was so strong that the exchangeable phase adsorption increase up to 80~90%. On the other hand, about 50% of copper was adsorbed in the carbonate occluded phase in single and competitive adsorptions. In the single adsorption the adsorption of carbonate occluded phase increased by 5% with the temperature increase and in the competitive adsorption the increase rate is about twice. The adsorption of zinc and copper on natural clays is an endothermic reaction with the exception of exchangeable phase adsorption.

• Journal of the Korean GEO-environmental Society
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• v.13 no.5
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• pp.35-40
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• 2012

In this study, adsorption characteristics of expanded graphite (EG) were investigated by a series of batch adsorption tests using p-Xylene as a model volatile organic compounds (VOCs). After acid treatment, graphite were expanded at various temperature from $600^{\circ}C$ to $1000^{\circ}C$ for one minute. The optimal temperature was $800^{\circ}C$, where the expansion ratio reached 195 times of original volume. The BET specific surface area of EG was $92.4m^2/g$, which was only 1/10 of granular activated carbon (GAC), however the adsorption of p-Xylene by EG was almost completed within 5 minutes while that of GAC continued for 7 days because the majority of pores of EG was consisted with meso- and macro-pores. According to the Langmuir isotherm analysis, the maximum specific adsorption of p-Xylene onto EG was 24.0 mg/L with the adsorption constant of 7.94. In conclusion, the adsorption capacity of EG was much less than that of GAC due to the significantly lower specific surface area, but the first order kinetic constant was more than 500 times larger than GAC. Overall, EG might be effective where the fast adsorption is required.