• Journal of the Korean Ceramic Society
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• v.38 no.4
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• pp.319-324
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• 2001

본 연구에서는 NaOH로 첨착시킨 활성탄의 표면특성변화와 H$_2$S 흡착능을 고찰하였다. 첨착시약으로 사용된 NaOH 용액의 농도는 1~8N이며, 활성탄의 입자크기는 8$\times$30mesh가 적용되었다. 실험결과는 첨착율이 0.87~5.8% 범위 내에서 증가할수록 BET 표면적은 1050$m^2$/g에서 783$m^2$/g로 감소하며, 표면산도는 0.541meq/g-AC에서 0meq/g-AC으로 감소하고, pH는 9.56에서 10.86으로 증가하는 것으로 밝혀졌다. 또한 NaOH로 첨착시킨 활성탄의 H$_2$S 평형흡착능을 보임으로써 비첨착활성탄에 비해 2~3배 높은 수준을 나타냄을 알 수 있었다.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2003.05a
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• pp.474-477
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• 2003

산성가스용 방독마스크 정화통은 활성탄에 정화제를 첨착시킨 첨착 활성탄을 사용하여 유해가스를 제거하여 왔으며, 일반적으로 알칼리제인 Ca(OH)$_2$를 첨착시켜 유독가스와 중화반응을 유도하여 왔다. 그러나 이들의 흡착제거 능력이 크지 않아 많은 양을 사용하여야 하는 문제점이 있었다. 따라서 정화통의 성능을 좌우하는 새로운 첨착물질을 선정하여야 고효율ㆍ저비용 정화통을 개발할 수 있으며, 본 연구에서는 이러한 첨착흡착제를 개발하여 이를 방독마스크 정화통에 적용하고자 하였다.(중략)

• Journal of Korean Society of Environmental Engineers
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• v.22 no.2
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• pp.203-210
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• 2000

The preparative methods of a chitosan-deposited activated carbon and its characteristics were studied by using three kinds of chitosan with different degree of deacetylation and average molecular weight. The procedure was consisted of the dissolution of chitosan into acid solution, impregnation of activated carbon, agitation, evaporation, and drying. When the chitosan-dissolved acid and its concentration, amounts of chitosan deposited, and agitation conditions were changed, the specific surface area, deposition state on surface, and stability were investigated, and amounts of Cr(VI) adsorbed was measured. In the preparation process, it was proper to agitate the chitosan-dissolved acetic acid solution at room temperature for 1hr. In the deposition of chitosan with low molecular weight, the specific surface area of activated carbon was greatly decreased even at low chitosan loading, but in the case of high molecular weight it was not nearly changed to 10wt% loading. It was known that chitosan was uniformly and physically deposited on activated carbon. The chitosan-deposited activated carbon was stable into the solution over about pH 6. The removal of Cr(VI) was remarkably enhanced by adding the adsorption function of chitosan to the surface of activated carbon with about 5wt% chitosan. It may be therefore used as an adsorbent for removing the pollutants in air and wastewater.

• Korean Chemical Engineering Research
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• v.61 no.3
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• pp.472-478
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• 2023

In this study, the acetaldehyde removal characteristics of activated carbon (AC) for air purifier filters were investigated using metal catalysts-impregnation and functional group-modification method. The AC with a high specific surface area(1700 m²/g) and micropores was prepared by KOH activation of coconut charcoal and the efficiency of catalyst and functional group immobilization was examined by varying the drying conditions within the pores after immersion. The physical properties of the prepared activated carbon were analyzed by BET, ICP, EA, and FT-IR, and the acetaldehyde adsorption performances were investigated using gas chromatography (GC) at various impregnation and modified conditions. As the concentration of impregnation solution increased, the amount of impregnated metal catalysts increased, while the specific surface area showed a decreasing trend. The adsorption tests of the metal catalyst-impregnated and functional group-modified activated carbons revealed that excellent adsorption performance in compositions MgO10@AC, CaO10@AC, EU10@AC, and H-U3N1@AC, respectively. The MgO10@AC, which showed the highest adsorption performance, had a breakthrough time of 533.8 minutes and adsorption capacity of 57.4 mg/g for acetaldehyde adsorption. It was found that the nano-sized MgO catalyst on the activated carbon improved the adsorption performance by interacting with carbonyl groups of acetaldehyde.

• Applied Chemistry for Engineering
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• v.16 no.3
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• pp.312-316
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• 2005

Adsorption characteristics of $CO_2$ on activated carbons were evaluated using dynamic adsorption method in a fixed bed with acid treatment, LiOH impregnation and water vapor supply. Physical and chemical properties of the activated carbons were measured using SEM, EDS, nitrogen adsorption, FTIR and XRD. Nitric acid treatment led to the decrease in BET surface area and the increase in oxygen content of virgin activated carbon, and it produced a new functional group that included nitrogen. For the reduction of BET surface area by LiOH impregnation, the nitric acid treated activated carbon (NAC) was less than the virgin activated carbon (AC). Large particles of LiOH were present on the carbon surface when the content of LiOH was over 2 wt%. The adsorbed amount of $CO_2$ on activated carbon in a fixed bed increased with the acid treatment, LiOH impregnation and water vapor supply. The XRD results indicated that LiOH was converted to $Li_2CO_3$ after the adsorption of $CO_2$ on LiOH precursor.

• Journal of the Korean Institute of Gas
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• v.7 no.1 s.18
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• pp.47-52
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• 2003

The adsorption characteristics of rert-butyl mercaptan(TBM) on base activated carbon and activated carbon impregnated with $CuCl_2$ or KI were studied. Adsorption of TBM on the surface of the KI or $CuCl_2$ impregnated activated carbon was detected by gas chromatograph equipped with a flame photometric detector. The amount of adsorption on those impregnated carbon found to be 7 or 8 times greater than on the non-impregnated activated carbon and varied according to the concentration of impregnated metal. FT-IR measurement showed that major reaction occuring on the surface of the catalytic adsorbent was dimerization of TBM into di-tert-butyl disulfide which had no stench.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05d
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• pp.88-94
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• 1996

원자력발전소의 공조계통에 설치되어 운영되는 기체 방사성물질 제거용 첨착 활성탄 탑내에서 균일한 공기 유속분포가 유지되고 있는지를 확인하기 위한 실험을 실시하였다. 본 실험에 사용되는 장비(Tester for Flow Distribution, 이하 TFD라 함)는 원자력발전소에서 사용하는 첨착 활성탄 필터(Adsorber)내의 흡착층을 모방하여 자체에서 제작하였으며, 시험조건들은 실제의 값을 기준으로 적용하였다. 각 위치에서의 보정된 용적 유속을 구하기 위해 자체에서 만든 "FLOWD"라는 계산프로그램을 사용하였으며, 입구 및 출구측 공간에 10" 간격으로 각 6개씩 유속 감지기를 설치하여 면속도를 구하였다. 각 지점에서의 면속도는 평균 0.24449m/s로 각 구간에서의 겉보기 면속도의 분포는 매우 균일한 값을 나타내었으며, 약 2% 이내의 편차로 활성탄 탑내에서의 공기의 흐름이 균일하게 통과함을 확인할 수 있었다.통과함을 확인할 수 있었다.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.4
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• pp.384-388
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• 2006

The adsorption ability of polar and toxic substance was greatly enhanced by treating activated carbon with acid solution and impregnating iron, copper, or silver by using in 0.1 M $FeSO_4{\cdot}7H_2O,\;CuSO_4{\cdot}5H_2O,\;AgNO_3$ 300 mL per activated carbon 50 g. Physical and chemical properties of the metal impregnated activated carbons were measured using specific surface area, pore volume and size distribution, scanning eletron microscope(SEM), adsorption isotherm. When activated carbon was treated with acid, the quantity of impregnated metal increased about 1.3 times since the micropores were converted to mesopores or macropores. Both the physical absorption by micropores and chemical absorption by metal ions could be achieved simultaneously with the metal impregnated activated carbon because the capacity of micro pores did not change even after metal ions were impregnated.

• Applied Chemistry for Engineering
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• v.32 no.6
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• pp.671-678
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• 2021

Effects of nitric acid treatment of an activated carbon and impregnation of metal chlorides on the activated carbon were investigated to improve ammonia adsorption performance. It was confirmed that functional groups such as hydroxyl and carboxyl groups were introduced onto a surface of the activated carbon with nitric acid treatment. Then, each metal chloride (NiCl₂, MgCl₂, CuCl₂, MnCl₂ or CoCl₂) was impregnated onto the surface-modified activated carbon using an ultrasonic impregnation method. The physicochemical properties and ammonia adsorption performance of various impregnated activated carbons were observed. Metal chlorides were well dispersed by sonication and evenly distributed on the surface of the activated carbon. Despite the reduced specific surface area and pore volume, the surface-modified activated carbon impregnated with metal chlorides exhibited excellent ammonia adsorption performance. In particular, HNO₃-NiCl₂ AC prepared by impregnating NiCl₂ showed the best ammonia adsorption capacity of 3.736 mmol·g^-1, which was improved by about 57 times compared to that of an untreated activated carbon (0.066 mmol·g^-1).

• Environmental engineer
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• v.23 s.238
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• pp.26-33
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• 2006