• 한국대기환경학회지
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• 제25권2호
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• pp.122-132
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• 2009

Adsorption of toluene by activated carbon fiber (ACF) coated with dielectric heating element and desorption by applying microwave were investigated. In order to prepare adsorbent so that VOC can be desorbed by microwave heating, fine dielectric heating element with nano size was coated on the surface of the ACF using hybrid binder. Eight adsorbents (ACF-DHE, Activated Carbon Fiber coated with Dielectric Heating Element) were prepared with different amount of dielectric heating element, kinds of hybrid binder, and solvent. In order to investigate adsorption characteristics, BET surface area, pore volume, and average pore size were measured for each adsorbent including ACF. Breakthrough experiments with toluene concentration, flow rate, bed length using fixed bed reactor were performed to investigate adsorbality of adsorbent, and results were compared with that of the ACF. Desorption reactor was constructed with modified microwave oven to investigate heating effect on ACF-DHE by applying microwave power. Each adsorbent saturated with toluene were put into desorption reactor. Composition of desorbed gas generated by applying controlled microwave power to reactor was measured. Up to now, hot air desorption method has been used. Experimental results showed that desorption method with new adsorbent prepared by coating dielectric heating element on ACF can be used for industrial application.

• 한국대기환경학회지
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• 제23권2호
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• pp.203-213
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• 2007

Numerical analysis has been performed to understand flow characteristics in the reactor with bag filters in an integrated adsorption/catalytic process which can treat dioxin and $NO_{x}$ together. Computational fluid dynamics technique was employed with Euler-Lagrangian model to consider flue gas and activated carbon particles simultaneously, so that residence time of flue gas and activated carbon particle could be obtained from the numerical analysis directly. The numerical analysis has been performed with different three particle sizes and compared each flow characteristics with particle's size. Fundamental flow patterns of flue gas and activated carbon particles, pressure distribution, residence time of flue gas and activated carbon particles, and distribution of activated carbon have been obtained from the numerical analysis. Flow patterns of flue gas and activated carbon particles in the reactor were very complicated and they moved along very various paths. Therefore, their residence time in the reactor was also various. The results obtained would be effectively used to estimate the removal efficiency in the reactor once the residence time is combined with the reaction equation.

• 한국대기환경학회지
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• 제15권2호
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• pp.191-199
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• 1999

This study evaluated the availability as an alternative adsorbent which is cheaper and more efficient than CuO/${\gamma}$-$Al_2O_3$ which have been studing vigorously to remove $SO_2$. Five adsorbents (CuO/${\gamma}$-$Al_2O_3$, Iron ore, Slag, LD slag, $Fe_2O_3$) was employed in a fixed bed reactor. $SO_2$ breakthrough curves were obtained as a function of temperature, initial gas velocity and particle size. Saturation capacities calculated by the numerical integration of breakthrough curves of $SO_2$ increased with increasing reaction temperature. $SO_2$ breakthrough curve equation of $Fe_2O_3$ for this system can be expressed as Kr=3,914,000 exp(-37,329.86/RT). By means of the breakthrough curve, the influence of bed height on breakthrough time was also estimated.

• Journal of the Korean Wood Science and Technology
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• 제35권4호
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• pp.29-37
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• 2007

탄화온도 차이에 따른 목질 탄화물의 중금속 흡착성 변화를 알아보기 위하여, 신갈나무(Quercus mongolica) 목부와 낙엽송(Larix kaempferi) 수피분말을 $400{\sim}900^{\circ}C$에서 탄화하였다. 목질 탄화물의 pH는 재료의 종류와 관계없이 탄화온도의 증가와 함께 증가하여 $900^{\circ}C$의 목탄 및 수피탄은 각각 10.8, 10.4를 나다내었다. 또한 탄화 온도 증가와 함께 탄소함량비가 증가하고 동일 탄화온도에서 목탄에 비해 수피탄의 탄소함량비가 큰 경향을 보였다. 액상흡착력을 나타내는 요오드흡착력은 목탄이 수피탄보다 다소 큰 경향을 나타내었다. 이러한 특성을 지닌 목탄과 수피탄에 의한 15ppm의 Cd, Zn 및 Cu 중금속용액에 대한 흡착제거율을 조사한 바, 높은 탄화온도에서 제조된 목탄과 수피탄일수록 높은 중금속제거율을 나타내었으며, 탄화물 종류에 있어서는 목탄이 수피탄 보다 높은 중금속 제거율을 나타내는 경향이 있었다. 특히 목탄의 경우, $500^{\circ}C$ 이상에서 제조된 탄화물 0.2 g의 사용으로 거의 100%에 가까운 제거율을 나타내었다. 한편 흡착질 종류에 있어서의 제거성능에는 다소 차이가 있으며, 본 연구에서 사용한 탄화물의 흡착성은 Cu>Cd>Zn 순으로 높았다. 이는 목탄과 같은 흡착제와 흡착의 대상이 되는 흡착질과의 물리 화학적 상호관계가 흡착에 영향을 주기 때문으로 목탄의 흡착효율을 높이기 위해서는 이에 대한 연구가 더 필요할 것으로 생각된다.

• 대한화학회지
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• 제17권1호
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• pp.53-59
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• 1973

우리나라 영산일 bentonite를 KF, $NH_{4}Cl$등의 염과 혼합하여 $200-500^{\circ}C$로 가열처리하여 수세 건조한 시료의 methylene blue 흡착능을 조사하였다. $NH_{4}Cl$를 혼합하여 처리하였을 경우에는 methylene blue 흡착능이 다소 개선되었다. KF를 혼합하여 처리하였을 경우에는$200-300^{\circ}C$의 처리에서 methylene blue의 흡착능이 원시료의 약1.7배까지 개선되었다. $FeSO_4$ 나 $Na_{2}CO_4$등의 염과 혼합하여 처리하였을 경우에는 오히려 methylene blue 흡착능이 감소되었다.

• Korean Chemical Engineering Research
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• 제50권2호
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• pp.244-250
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• 2012

MEA(monoethanolamine)와 PZ(piperazine)를 함침한 성형 제올라이트 13X 흡착제를 이용하여 연소배가스 중 이산화탄소를 분리하고자 하였다. 이를 위해 MEA, PZ를 각각 30, 50, 70 wt%로 성형 제올라이트에 함침하였다. 함침된 성형 제올라이트 13X 흡착제에 대한 물성 평가를 위해 XRD, FT-IR, BET를 이용하였다. 이산화탄소 분리특성을 조사하기 위하여, 성형 제올라이트, MEA 함침 성형 제올라이트, PZ 함침 성형 제올라이트에 대하여 25, 50, $75^{\circ}C$에서 흡착능을 조사하였다. 아민 함침 성형 제올라이트 흡착제는 온도가 증가할수록 흡착능은 감소한다. 최종적으로 연소배가스의 배출온도인 $50^{\circ}C$에서 흡착능을 비교할 때, PZ가 함침된 성형 제올라이트는 성형 제올라이트보다 1.8배 그리고 MEA 함침된 성형 제올라이트보다 20배 이상의 이산화탄소 흡착능을 보였다.

• 대한의용생체공학회:의공학회지
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• 제7권2호
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• pp.183-190
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• 1986

Microspheres are expected to be applied to biomedical areas such as solid-phase immunoassays, drug delivery systems, immunomagnetic cell separation. To synthesize microspheres for biomedical application, "two stage shot growth method" was developed. The uniformity ratio of synthesized microspheres was always smaller than 1.05. And the surface charge density (or the number of ionizable functional groups) of the microspheres synthesized by "two stage shot growth method" was 6~13 times higher than that of the microspheres synthesized by conventional seeded batch copolymerization. As a previous step for biomedical application, adsorption experiments of bovine albumin on microspheres were carried out under various conditions. The maximum adsorbed amount was obtained in the neighborhood of pH 4.5. Isoelectric point of bovine albumin is pH 5.0, so experimental result shows that it shifted to acid area. The adsorption isotherm was obtained, the plateau region was always reached at 2.Og/L (bulk concentration of bovine albumin).The effect of the kind and the amount of surface functional group was also examined.p was also examined.

• Carbon letters
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• 제2권2호
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• pp.91-98
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• 2001

Porous carbons have been prepared from different parts of banana stems using two different routes, viz., by pyrolysing the mass at different temperatures as well as by treating the dried mass with chemicals followed by pyrolysis. The pyrolysis behaviour of all these materials has been studied up to $1000^{\circ}C$. Samples treated with acids exhibit more increase in surface area as compared to those treated with alkalies or salts. Analysis of BET surface area shows that the carbon prepared at low temperature shows mixed porosity, i.e., micro and mesopores. Samples heated to high temperature above $700^{\circ}C$ show decrease in macroporosity and increase in microporosity. Liquid adsorption studies have been made using methylene blue and heavy oil. The activated carbons so prepared exhibit higher oil adsorption mainly in the macro and mesopores.

• 대한의용생체공학회:의공학회지
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• 제36권1호
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• pp.1-6
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• 2015

This study aims to design a monolayer cell adsorption apparatus that would help to produce high-quality slides for Liquid-Based Cytology (LBC) of an early cancer diagnosis for human bodies. The LBC collects exfoliated cells of human bodies and spreads the cells on the slides. Through processes of dyeing and cytological examination, the LBC screens for cancers in early stage. In this study, both of a cell suction module and a cell adsorption module, which are the key elements of the monolayer cell adsorption apparatus, were developed, and using those modules, the study set, first, conditions to help both GYN and NON-GYN apply principal cells without de-endothelialization before conducting its own analysis on the utility. As a results, for GYN, apparatus was determined to be able to produce high-quality slides under the condition of 4 and for NON-GYN, the apparatus would come up with other slides of high-quality under the condition of 2. The study carried out a repetitive test on selected conditions and proved 96% of the repetitive success rate. By the results of what has been learned so far, the study presents that the apparatus has a possibility to replace device from South Korea as one of those other currently-applied systems to run the LBC and that the system will also present a new paradigm for cancer diagnosis as it makes a contribution to the improvement in the LBC.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권7호
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• pp.81-89
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• 2013

Concerns have been raised over the impact of nano materials on soil and groundwater environment with the increasing attention to the potential applications of carbon nano materials in various fields. Particularly, carbon nano materials introduced into water environment readily make complexes with humic acid (HA) due to their hydrophobic nature, so there have been increasing numbers of studies on the interaction between HA and carbon nano materials. In this study, we investigated the solubility of HA and multiwalled carbon nanotubes (MWCNT) in three different surfactant solutions of sodium dodecyl sulfate (SDS), Brij 30 and Triton X-100, and evaluated whether the HA can be effectively desorbed from the surface of MWCNT by surfactant. The objective of this study was to determine the optimal adsorption condition for HA to MWCNT. Futhermore, sodium dodecyl sulfate (SDS), Brij 30, Triton X-100 were used to elucidate the effect of desorption and separation on adsorbed HA on MWCNT. As a result, HA solution with 12.7 mg of total organic carbon (TOC) and 5 mg of MWCNT showed the highest adsorption capacity at pH 3 reacted for 72 hrs. Weight solubilizing ratio (WSR) of surfactants on HA and MWCNT was calculated. HA had approximately 2 times lower adsorption capacity for the applied three surfactants compared to those of MWCNT, implying that the desorption of HA may occur from the HA/MWCNT complex. According to the results of adsorption isotherm and weight solubilizing ratio (WSR), the most effective surfactants was the SDS 1% soluiton, showing 53.63% desorption of HA at pH 3.