• 한국세라믹학회지
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• 제40권5호
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• pp.468-474
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• 2003

안정화 PAN(Polyacronitrile)계 섬유를 이용하여 물리적인 방법과 화학적인 방법으로 활성탄소섬유(Activated Carbon Fibers)를 제조하고, 그 특성을 비교평가 하였다. 본 연구에서는 안정화 PAN계 섬유를 수증기 및 $CO_2$를 이용한 물리적 활성화와 KOH를 이용한 화학적 활성화에 의해 여러 등급의 활성탄소섬유를 제조하였고, 비표면적, 요오드흡착량, 미세구조, 세공구조 등을 측정하였다. 물리적 활성화 방법에는 수증기와 $CO_2$가 사용되었는데, 수증기활성화의 경우 99$0^{\circ}C$의 활성화 온도에서 1635 m$^2$/g의 비표면적을 나타내었고, $CO_2$ 활성화의 경우에는 99$0^{\circ}C$의 활성화 온도에서 671 m$^2$/g의 비표면적을 나타내었다. KOH를 이용한 화학적 활성화 방법에서는 KOH와 안정화 PAN계 탄소섬유의 비가 1.5 : 1인 경우 90$0^{\circ}C$의 활성화 온도에서 3179 m$^2$/g의 비표면적을 나타내었다. 물리적 활성화와 화학적 활성화로 제조된 활성탄소섬유의 질소흡착등온선의 결과로 보면 type I의 형태와 type I에서 type II로의 전이형태의 등온흡착곡선을 나타내었다.

• Carbon letters
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• 제5권2호
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• pp.55-61
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• 2004

Adsorption isotherms of p-nitrophenol from its aqueous solutions on two samples of activated carbon fibres and two samples of granulated activated carbons have been determined in the concentration range 40~800 mg/L (ppm). The surface of these carbons was modified by oxidation with nitric acid and oxygen gas, and by degassing the carbon surface under vacuum at temperatures of $400^{\circ}C$, $650^{\circ}C$ and $950^{\circ}C$. The oxidation of carbon enhances the amount of carbon-oxygen surface groups, while degassing decreases the amount of these surface groups. The adsorption of p-nitrophenol does not depend upon the surface area alone but appears to be influenced by the presence of oxygen groups on the carbon surface. The adsorption decreases on oxidation while the degassing of the carbon surface enhances the adsorption. The decrease in adsorption depends upon the strength of the oxidative treatment being much larger in case of the oxidation with nitric acid, while the decrease in adsorption on degassing depends upon the temperature of degassing. The results show that while the presence of acidic surface groups which are evolved as $CO_2$ on degassing suppress the adsorption of p-nitrophenol, the presence of non acidic surface groups which are evolved as CO on degassing tend to enhance the adsorption. Suitable mechanisms compatible with the results have been presented.

• 한국축산식품학회지
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• 제22권2호
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• pp.145-150
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• 2002

본 연구는 돼지사료내 활성탄 첨가 급여가 돈육의 품질에 미치는 효과를 알아보고자 등심과 삼겹부위를 이용하여 일반성분, 조직적 특성, 관능적 특성 및 지방산을 분석하였다. 분석결과 활성탄 첨가급여로 인해 일반성분, pH, 가열감량에 있어서는 별다른 영향을 미치지 않았지만, 육의 기호성과 조직적 특성에는 영향을 미치는 것으로 나타났는데, 특히 경도의 경우 활성탄 첨가구가 대조구에 비해 유의적으로(p<0.05) 높게 나타났다(p<0.05). 지방산 분석결과, 등심부위의 palmitic acid 함량은 대조구가 활성탄 첨가급여구에 비해 유의적으로 높은 반면, oleic acid, linoleic acid 및 linolenic acid 함량은 활성탄 첨가급여구가 유의적으로(p<0.05) 높게 나타났다. 삼겹부위에서는 대조구가 활성탄 첨가급여구에 비해 stearic acid 함량이 유의적으로(p<0.05) 높게 나타났다. 이상의 결과를 종합해 볼 때 돼지사료내 활성탄을 첨가함으로써 돈육의 품질에 미치는 효과는 미미했으나, 지방산 조성에 있어서는 불포화 지방산의 함량이 증가하는 것으로 보아, 이에 대한 명확한 연구를 위해서는 조사두수의 확대와 급여수준에 대한 연구가 더 필요할 것으로 사료된다.

• KSBB Journal
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• 제19권2호
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• pp.104-109
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• 2004

정수용 입상활성탄 (granular activated carbon, GAC)으로 사용되는 식물계와 석탄계 활성탄의 미생물 재생장 현상을 파악하고 비교하기 위해 활성탄 칼럼을 대상으로, 유입수와 유출수 비교와 함께 활성탄 상의 종속영양세균의 분포와 활성을 분석하였다. 활성탄 칼럼은 총유기탄소와 잔류염소를 잘 제거하였으며 이온은 잘 제거하지 못하는 것을 알 수 있었으며, 칼럼 유출수의 세균수는 10일째 파과 (breakthrough)가 발생한 후 증가하여 최종적으로 석탄계와 식물계 활성탄에서 각각 1.1 ${\times}$ $10^3$, 6.2 ${\times}$ $10^2$ CFU/mL로 나타났다. 칼럼 내부 활성탄 상의 미생물 활성은 GAC-C가 15.35~29.06$\mu\textrm{g}$ INT-formazan/g-GAC/h이었고, 세균수와 세균활성 모두 석탄계가 조금 높았다. 입상활성탄 상의 미생물 재생장 현상이 확인되었고, 석탄계 활성탄이 야자계 활성탄보다 미생물 재생장 유발 효과가 큰 것으로 판명되었으며, 활성탄 상의 세균에 의한 유기물 제거능력이 확인되었다.

• 농업과학연구
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• 제7권1호
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• pp.27-32
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• 1980

활성탄(活性炭)을 처리(處理)하여 제초제(除草劑)의 약해경감효과(藥害輕減效果)를 구명(究明)하기 위하여 공시채소(供試菜蔬) 배추, 고추 및 토마토를 파종(播種)한 후(後)에 활성탄(活性炭) 0, 5, 10kg/10a을 파종직후(播種直後) 토양전면(土壤全面)에 처리(處理)하였다. 제초제(除草劑)는 Linuron 50, 75g/10a와 Napropamide 150, 225g/10a을 각각(各各) 처리(處理)하였고 출현율(出現率)과 건물중(乾物重)을 조사(調査)하였다. 1. Linuron 50, 75g/10a을 배추에 처리(處理)하였을 때 배추는 심(甚)한 약해(藥害)로 인하여 전부(全部) 고사(枯死)되었지만 활성탄(活性炭) 처리(處理)에 의하여 약해(藥害)가 경감(輕減)되었다. 그러나 Napropamide을 처리(處理)한 경우에는 약해(藥害)가 거의 없었기 때문에 활성탄(活性炭)의 효과(效果)도 크게 기대(期待)할 수 없었다. 2. Linuron을 고추에 처리(處理)했을 때 심(甚)한 약해(藥害)를 보였으나 활성탄(活性炭) 처리(處理)에 의하여 약해(藥害)는 경감(輕減)되어 출현율(出現率)이나 건물중(乾物重)이 무처리구(無處理區)와 큰 차이(差異)가 없었으며 Napropamide 처리구(處理區)에서 고추는 약해(藥害)가 적게 나타났지만 활성탄(活性炭) 처리(處理)로 인하여 약해(藥害)가 경감(輕減)되었다. 3. 토마토도 Linuron에 대하여 심(甚한) 약해(藥害)를 보였으나 활성탄(活性炭)에 의한 약해경감효과(藥害輕減效果)가 현저했다. 그러나 토마토는 Napropamide에 의하여 약간의 약해(藥害)를 받았으며 활성탄(活性炭)의 약해경감효과(藥害輕減效果)도 미흡(未洽)하였다.

• 상하수도학회지
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• 제22권5호
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• pp.511-516
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• 2008

Since 1989, Advanced drinking water treatment processes began to build in Korea, especially the water treatment plants around the Nak-dong river stream due to sequential pollutant accidents. Moreover, Advanced drinking water treatment processes, ozone and GAC, are again to be built in water treatment plants around Han-river stream to control taste and odor, micro pollutants. However, there are still a lot of discussion to decide the processes to apply for advanced treatment. Thus there are still need to understand clearly on the cost evaluation of each advanced treatment processes. The cost evaluation was accomplished based on the data of six water treatment plants which are currently being either operating or constructing. Exceptionally, PAC(Powdered Activated Carbon) process was evaluated with cost estimation from construction company. The capital cost per unit volume of ozone process was significantly decreased as the treatment capacity increased. The capital cost was in the order of GAC, ozone and GAC. The operation cost decreased in the order of PAC, GAC and ozone. The total cost considering present value shows that ozone process covers 84% of ozone and GAC process for $30,000m^3/d$ capacity while it covers less than 35% for over 140 thousands $m^3/d$ capacity. Comparing GAC only, and ozone/GAC process, ozone/GAC process is more cost effective for high capacity water treatment plant.

• 상하수도학회지
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• 제12권4호
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• pp.33-42
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• 1998

The optimum design and preliminary cost estimations of air stripping towers ASTs with granular activated carbon adsorption (GAC) systems as the off-gas treatment were done and compared to liquid-phase GAC system. The optimum design and preliminary cost estimations were done for either single or multicomponent systems. A computer program was developed for this study. 15 single compounds and their multicomponent systems were studies. Even with off-gas treatment, AST was generally a less expensive process for treatment of volatile organics than liquid-phase GAC system. Treatment costs of small systems were sensitive to system capacity. Accumulative effect of treatment costs was found in multicomponent systems. The cost of a multicomponent system was highly dependent on the least strippable component in ASTs even with gas-phase GAC or the least adsorbable component in liquid-phase GAC system.

• 한국결정성장학회지
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• 제14권2호
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• pp.37-46
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• 2004

The electrochemical adsorption of the Ag ions from aqueous solution on pelletized activated carbon monolith was investigated over wide range of operation time. The adsorption capacities of pelletized activated carbon monolith are associated with their internal porosity and are related properties such as surface area, pore size distribution. The chemical industry generates wastewater that contains toxic matters like heavy metals in small concentrations so that their economic recovery is not feasible. But, the method using activated carbon monolith can be used to withdrawal of heavy metals in waste water. After the electrochemical treatment, the quantitative properties in Ag ion solutions are also examined by pH concentration and studied elemental analysis by ICP-Atomic Emission Spectrometer and Energy Disperse X-ray (EDX) spectra. It is consider that the pH is very important factor at the reason of water pollutant with increasing acidity in industrial field. The result of quantitative analysis using Inductively Coupled Plasma-Atomic Emission Spectrometer of metal after electrochemical reaction in Ag ions solution depending on time are shown that the amount of Ag ions deposited was decreased with growth of Ag particles on the carbon surfaces as increasing electrochemically treated time. And, surface morphologies are investigated by scanning electron microscopy (SEM) to explain the changes in adsorption properties.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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• pp.219.2-219.2
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• 2011

The oxyfluorination effects of electrospun carbon nanofibers (OFACFs) were investigated for $CO_2$ storage. Carbon nanofibers were prepared form poly acrylonitrile / N,N-dimethylformamide solution through electrospinning method and heat treatment. Chemical activation of carbon nanofibers were carried out in order to improve the pore structure. And the surface modification of activated carbon nanofibers was conducted by oxyfluorination to improve the $CO_2$ storage on effect of introduced functional groups. The samples were labeled CF (electrospun carbon nanofiber), ACF (activated carbon nanofibers), OFACF-1 ($F_2:O_2$ = 3:7), OFACF-2 ($F_2:O_2$ = 5:5) and OFACF-3 ($F_2:O_2$ = 7:3). The functional group of OFACFs was investigated by x-ray photoelectron spectroscopy analysis. The specific surface area, pore volume and pore size of OFACFs were calculated and pore shape was estimated by the BET equation. Through the adsorption isotherm, the specific surface area and pore volume significantly decreased by oxyfluorination.

• Environmental Engineering Research
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• 제12권1호
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• pp.1-7
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• 2007

Most of the herb residue producing from oriental medical clinics(OMC) and hospitals(OMH) is wasted in Korea. To develop of adsorbent for removing heavy metal from wastewater, the various pre-treatment methods of the herb residue were evaluated by potentiometric titration, Freundlich isotherm adsorption test and the kinetic adsorption test. The herb residue was pre-treated for increasing the adsorption capacity by cleaning with distilled water, 0.1 N HCl and 0.1 N NaOH and by heating at $370^{\circ}C$ for 30 min. It showed a typical weak acid-weak base titration curve and a short pH break like commercial activated carbon during photentiometric titration of pre-treated herb residue. The log-log plots in the Freundlich isotherm test were linear on the herb residue pre-treated with NaOH or HCl like commercial activated carbon. The adsorption capacity(qe) in the Freundlich isotherm test for $Cr^{6+}$ was 1.5 times higher in the pre-treated herb residue with HCl than in activated carbon. On the other hand the herb residue pre-treated with NaOH showed the good adsorption capacities for $Pb^{2+}$, $Cu^{2+}$ and $Cd^{2+}$ even though those adsorption capacities were lower than that of activated carbon. In kinetic test, most of heavy metals removed within the first 10 min of contact and then approached to equilibrium with increasing contact time. The removal rate of heavy metals increased with an increase of the amount of adsorbent. Likewise, the removal rates of heavy metals were higher in the herb residue pre-treated with NaOH than in that pre-treated with HCl. The adsorption preference of herb residues pre-treated with NaOH or HCl was $Pb^{2+}>Cu^{2+}$ or $Cd^{2+}>Cr^{6+}$ in the order. Conclusively, the herb residue can be used as an alternative adsorbent for the removal of heavy metals depending on pr-treatment methods.