• Journal of Microbiology and Biotechnology
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• 제26권1호
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• pp.99-109
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• 2016

We investigated the relation between the presence of geosmin in water and the bacterial community structure within the granular activated carbon (GAC) system of water treatment plants in South Korea. GAC samples were collected in May and August of 2014 at three water treatment plants (Sungnam, Koyang, and Yeoncho in Korea). Dissolved organic carbon and geosmin were analyzed before and after GAC treatment. Geosmin was found in raw water from Sungnam and Koyang water treatment plants but not in that from Yeoncho water treatment plant. Interestingly, but not surprisingly, the 16S rRNA clone library indicated that the bacterial communities from the Sungnam and Koyang GAC systems were closely related to geosmin-degrading bacteria. Based on the phylogenetic tree and multidimensional scaling plot, bacterial clones from GAC under the influence of geosmin were clustered with Variovorax paradoxus strain DB 9b and Comamonas sp. DB mg. In other words, the presence of geosmin in water might have inevitably contributed to the growth of geosmin degraders within the respective GAC system.

• Korean Chemical Engineering Research
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• 제46권6호
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• pp.1130-1134
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• 2008

아세트산은 테레프탈산 제조 공정에서 용매로 사용되며, 사용된 아세트산은 반응 후 증류 공정을 통하여 분리 회수된다. 그러나 소량의 아세트산은 그대로 폐수에 유입되어 버려지는데, 흡착공정을 이용하면 소량의 아세트산을 회수하여 다시 재사용할 수 있다. 본 연구에서는 활성탄을 아세트산 흡착제로 활용하여 상용활성탄의 아세트산 흡착능과 흡착능에 대한 온도 및 흡착제 산처리 효과를 살펴보았다. 활성탄의 아세트산 흡착능은 흡착 키네틱 실험으로 관찰한 결과, 303 K에서는 0.176 mmol/g의 흡착능을 보였으나, 343 K에서는 0.118 mmol/g으로 흡착능이 떨어졌다. 즉, 온도가 증가하면 활성탄의 아세트산 흡착능은 감소하는 결과가 나타났다. 산처리실험에서는 활성탄 표면을 염산 혹은 옥살산으로 처리할 경우, 활성탄의 아세트산 흡착능이 소폭 증가하였다. 이는 산처리로 인해 활성탄 표면에 카르복실산, 혹은 페놀 수산화기 등 표면 관능기가 증가하였기 때문인 것으로 보인다. 아세트산 탈착 실험에서는 정량분석결과, 흡착된 아세트산의 89% 정도가 탈착되었다.

• 에너지공학
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• 제14권2호
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• pp.133-139
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• 2005

도장공정에서 발생하는 VOC의 처리를 위한 활성탄-광촉매 복합시스템을 제안하였고, VOC제거성능을 실험적으로 평가하였다. 활성탄 합은 톨루엔 흡착특성에 근거하여 설계하였고, 광촉매 시스템은 $TiO_2/SiO_2$ 유동층 반응기와 $TiO_2$코팅된 필터의 연계시스템으로 설계하였다. 본 활성탄-광촉매 복합시스템은 서로 다른 VOC 화학종 및 농도에 따라 $75\~100\%$에 이르는 VOC제거효율을 보여주었다.

• 상하수도학회지
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• 제26권1호
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• pp.77-85
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• 2012

The present study investigates treatment methods for removal of arsenic from wastewater. The granular activated carbon (GAC) with the coating of iron chloride ($FeCl_3$) was used for the treatment of a low concentration of arsenic from wastewater. Batch experiments were performed to investigate the synthesis of Fe-GAC (Iron coated granular activated carbon), effects of pH, adsorption kinetics and the Langmuir model. The synthesized Fe-GAC with 0.1 M $FeCl_3$ shows best removal efficiency. Adsorption studies were carried out in the optimum pH range of 4-6 for arsenic removal. The Fe-GAC showed promising results by removing 99.4% of arsenic. In the adsorption isotherm studies, the observed data fitted well with the Langmuir models. In continuous column study showed that As(V) could be removed to below 0.25 mg/L within 1,020 pore volume. Our results suggest that the surface modified granular activated carbon treated with $FeCl_3$ for effective removal of arsenic from wastewater.

• 자원리싸이클링
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• 제9권6호
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• pp.9-14
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• 2000

CSAC와 WPAC의 흡착특성을 보면 H공장 2차 처리수와 D공장 배출수에 함유된 ABS흡착에서 얻어진 Freundlich흡착등온식은 WPAC인 경우 q=23.12 $C^{ 0.42}$, q=18.32 $C^{0.38}$ 이고 CSAC인 경우 각각 $q=36.76C^{1.37}$ , q=26.67 $C^{0.42}$ 이었다. H공장 방류수의 파과점은 CSAC인 경우 680분이었고 WPAC는 610분이었다. 한편 D공장 배출수의 파과점은 CSAC인 경우 720분이었고 WPAC은 640분이었다. 이상의 결과로부터 CSAC 대체물로서 WPAC이 가능성이 있을 것으로 생각된다.

• 한국수소및신에너지학회논문집
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• 제32권4호
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• pp.256-262
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• 2021

A carbon felt electrode was prepared using ozone and ammonia sequential treatment and applied as an electrode for a vanadium redox flow battery (VRFB). The physical and electrochemical analyses demonstrate that the oxygen groups facilitate nitrogen doping in the carbon felt. Carbon felt (J5O3+NH3), which was subjected to ammonia heat treatment after ozone treatment, showed higher oxygen and nitrogen contents than carbon felt (J5NH3+O3), which was subjected to ammonia heat treatment first and then ozone treatment. From the charging/discharging of VRFB, the J5O3+NH3 carbon felt electrode showed 14.4 Ah/L discharge capacity at a current density of 150 mA /cm², which was 15% and 33% higher than that of J5NH3+O3 and non-activated carbon felt (J5), respectively. These results show that ozone and ammonia sequential treatment is an effective carbon felt activation method to increase the performance of the vanadium redox flow battery.

• Carbon letters
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• 제1권3_4호
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• pp.154-157
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• 2001

Composite adsorbents were prepared by mixing water plant sludge with phenolic resin having the ratio of 1 : 1, 1 : 2, and 1 : 3 respectively, curing from $100^{\circ}C$ to $170^{\circ}C$ under $N_2$ atmosphere, and then activating with $N_2$ at $700^{\circ}C$. Thermal property, specific surface area and morphology of the composite adsorbents as well as their precursors were measured by TGA, BET and SEM respectively. Removal efficiency of the composite adsorbents to ${NH_4}^+$ and TOC was compared with those of commercial zeolite and activated carbon. The adsorbents presented very promising TOC removal efficiency of 98%, which was identical level to that of commercial activated carbon while they displayed removal efficiency, only 32%, of ${NH_4}^+$. Therefore, this composite adsorbent considered as the alternative material of commercial activated carbon, used as an expensive removal agent of organic substances and THM in water treatment plant and it also suggested a possibility of practical application in other processes.

• 대한환경공학회지
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• 제27권12호
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• pp.1311-1320
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• 2005

본 연구에서는 pilot 규모의 활성탄 공정을 운전하면서 입상활성탄(granular activated carbon: GAC) 단계에서부터 생물활성탄(biological activated carbon: BAC) 단계로 전환되고 난 후 까지 활성탄 재질별로 유기물 제거능과 미생물 군집특성을 함께 조사하였다. 활성탄 재질별 유기물 흡착능은 석탄계 재질의 활성탄이 가장 우수하였고, bed volume 20,000 이후부터는 3가지 활성탄들이 정성상태에 도달하였다. 부착세균의 생체량과 생산력 또한 석탄계 재질 활성탄에서 가장 높은 것으로 나타났으며, heterotrophic plate count(HPC), eubacteria(EUB), 4,6-diamidino-2-phenylindole(DAPI) 및 생산력은 각각 $0.95{\times}10^7{\sim}52.4{\times}10^7$ CFU/g, $3.8{\times}10^8{\sim}134.2{\times}10^8$ cell/g, $7.0{\times}10^8{\sim}250.2{\times}10^8$ cell/g 및 $1.2{\sim}3.4\;mg{\cdot}C/m^3{\cdot}h$의 범위로 나타났다. 그리고 부착세균의 생체량과 생산력은 모두 bed volume 20,000 이후부터 증가하는 경향을 보였다. 활성탄 재질별 부착세균 생체량과 세균 생산력에 대한 동화가능한 유기탄소(assimilable organic carbon: AOC) 제거율과의 상관성 평가에서는 석탄계 재질 활성탄이 가장 양호한 상관성을 보였으며, 항목별로는 세균 생산력에 대한 상관성이 상대적으로 높은 것으로 나타났다. Fluorescent in situ hybridization(FISH)에 의한 세균군집 구조 조사결과, bed volume 20,000까지는 모든 활성탄에서 $\alpha$ 그룹($\alpha$-proteobacteria)과 other bacteria가 우점하였고, bed volume 20,000 이상에서는 석탄계 재질 환성탄에서는 $\beta$ 그룹($\beta$-proteobacteria)과 $\gamma$ 그룹($\gamma$-proteobacteria)의 우점비율이 상승하였으나, 야자계와 목탄계에서는 $\alpha,\;\beta$ 및 $\gamma$ 그룹의 우점비율이 상승하는 것으로 조사되었다.

• Carbon letters
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• 제7권3호
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• pp.180-187
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• 2006

The treatment of piggery wastes was carried out at pilot scale using a multilayered metal-activated carbon system followed by carbon bed filtration. The physicochemical properties were obtained from treated samples with aqueous solutions containing metallic ions such as $Ag^+$, $Cu^{2+}$, $Na^+$, $K^+$ and $Mn^{2+}$, which main obsevations are subjected to inspect surface properties, color removal properties by Uv/Vis and EDX. Multilayered metal-activated carbons were contacted with waste water to investigation of the simultaneous catalytic effect for the COD, BOD, T-N and T-P removal. The removal results for the piggery waste using multilayered metal-activated carbon bed was achieved the satisfactory removal performance under permitted values of Ministry of Environment of Korea. The high efficiency of the multilayered metal-activated carbon bed was determined by the performance of this material for trapping, catalytic effect and adsorption of organic solid particles.

• 한국산업보건학회지
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• 제5권2호
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• pp.119-127
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• 1995

The purpose of this study was to determine the effects of surface-treatment by zinc salts on break-through and adsorption capacity of toluene. Firstly, the coconut activated carbon treated the surface with zinc salts, were exposed by the spike sample(toluene, 69.02ppm, $260.1mg/m^3$), and then the effects of zinc salts were examined by using the gas adsorption kinetics. The results obtained were as follows : 1) BET(Brumaure Emmett Teller) surface area were $954.4m^3/g$ in coconut activated carbon treated with 0.0001 N $Zn(NO_3)_3$ $6H_2O$, and $830.3m^2/g$ in coconut activated carbon treated with 0.0001 N $ZnCl_2$. 2) Migration was decreased in coconut activated carbon treated with the thin level of zinc salts. 3) Breakthrough volume were 73.07 L in coconut activated carbon treated with 0.0001 N $Zn(NO_3)_3$ $6H_2O$, and 72.76 L in charcoal treated with 0.0001 N $ZnCl_2$. 4) ${\tau}$ values(the time required for 50% breakthrough) were 1046.1 min in coconut activated carbon treated with 0.0001 N $ZnCl_2$ and 921.2 min in coconut activated carbon treated with 0.0001 N $Zn(NO_3)_3$ $6H_2O$. 5) Maximum adsorption capacity was 53.9 mg/tube in coconut activated carbon treated with 0.0001 N $ZnCl_2$ and 47.4 mg/tube in coconut activated carbon treated with 0.0001 N $Zn(NO_3)_3$ $6H_2O$. In conclusion, the coconut activated carbon treated the surface with the thin concentration of zinc salts, decreased the breakthrough and increased the BET surface area and the adsorption capacity in case of sampling airborne toluene.