• Journal of the Korea Safety Management & Science
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• v.2 no.2
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• pp.95-108
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• 2000

Electrochemical charateristics of activated carbon fiber cloth(ACFC) electrode were studied with propylene carbonate(PC), ${\gamma}$-butyrolactone(GBL) and N,N-dimethyl-formamide(DMF) as a solvent and tetraethylammoniumtetrafluoroborate(TEABF$_4$), tetraethylammoniumhexafluorophosphate(TEABF$_{6}$), tetrabutylammoniumtetrafluoroborate(TBABF$_4$) and tetrabutylammonium hexafluorophosphate(TBAPF$_6$) as an electrolytes(active material). The concentrations of electrolytes were in the range of 0.2~1.2 N, the volume ratios of PC and DMF as a mixed solvent system, were 90：10, 80：20, 70：30, 60：40, 50：50, and 40：60 vol%. Electrochemical characteristics such as electric conductivity, internal resistance, and electric capacitance of fabricated unit cells were measured after the moisture of activated material was removed with molecular sieve. Electrochemical characteristics were better in mixed solvents system than in mono solvent system. The mono solvent system of 1.0 N electrolyte of GBL/TEABF$_4$ with activated carbon cloth electrodes showed better result but the mixed solvent system with PC and DMF/TEABF$_4$(50：50 vol%) and the concentration of 1.0 N electrolyte showed the best characteristics. Internal resistance was 3.47 $\Omega$ and specific capacitance was 19.1 F/g respectively.y.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.25-26
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• 2021

Due to COVID-19, the spread of non-face-to-face culture is increasing the time spent indoors. Accordingly, it is necessary to reduce indoor air pollutants. Also, among building materials, there are paints. As the number of coatings increases, the coating film becomes thick, and there is a risk of cracking and falling off. Therefore, this study is to examine the adsorption properties of indoor air pollutants according to the number of coatings of a paint mixed with powdered activated carbon. In the experimental plan, the addition ratio of powdered activated carbon was selected as 30%, and the number of coatings was selected as primcoating, second coat, and finishing coat, and the concentration of formaldehyde and volatile organic compounds were measured. As a result, as the number of coatings increased, the concentration of formaldehyde and volatile organic compounds tended to decrease. This is considered to be due to the fact that not only the physical adsorption acted by the internal pores of the powdered activated carbon, but also because a lot of powdered activated carbon was present on the painted surface as the coating film was formed. However, since it is judged that there is an error in the concentration due to the inflow of external air as the chamber cover is opened to put the test object in the adsorption test process, it is considered that the experimental method needs to be supplemented.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.1
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• pp.133-139
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• 2000

In this study, activated carbon was prepared from solid residue after lignin pyrolysis by using zinc chloride as an activation agent. The steam activation method was adopted to manufacture activated carbon from solid residue after lignin pyrolysis. The effect of process operation variables such as activation temperature, activation time and mass of activation agent added to char on the pore structure and specific surface area of the activated carbon was investigated. Activated carbon with high surface area and well-developed pore structure could be prepared, when solid residue after lignin pyrolysis was mixed with zinc chloride of 300 wt% and then the mixture was activated for 1 hour at $1000^{\circ}C$ in a stream of nitrogen.

• Carbon letters
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• v.4 no.4
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• pp.168-174
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• 2003

Silver nitrate ($AgNO_3$) powder was mixed into a reformed pitch precursor. Then, the silver-containing pitch was melt spun to form round and "C" shape fibers. A wire mesh was inserted prior to the nozzle to improve the spinnability of the silvercontaining precursor pitch. Silver particles in the carbon fibers (CFs) were detected by XRD and TEM. These tests showed that silver particles were uniformly distributed and the total amount of silver remained constant during stabilization and carbonization. Next, the silver-containing CFs were activated by steam diluted in nitrogen gas. Silver particles accelerated the activation rate, but the specific surface areas of the silver-containing ACFs were similar to those of non-silver containing ACFs at the same burn-off levels. The specific surface area of the C-shaped activated carbon fibers was larger than that of the round activated carbon fibers. The likely reason is that the surface area of a C-shaped CF is about two times larger than that of a round CF when equivalent cross-sectional areas are compared. A small amount of silver particles in the periphery of the CFs was removed during the activation, but the remainder of silver was stayed within the ACFs.

• Proceedings of the Safety Management and Science Conference
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• 2001.11a
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• pp.157-160
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• 2001

The electrodes were fabricated by compounding the commercial activated carbons and additives of conducting polymer with PVdF mono binder and PVdF-PVP mixed binders. The best performance of the electrodes fabricated with activated carbon(BP-20) and PVdF-PVP mixed binders showed in 88wt. ％ BP-20. 7wt. ％ conducting polymer and 5wt.％ PVdF-PVP mixed binder. The electrode exhibited excellent electrochemical characteristics having 8.16 W.h/kg of energy density, 34.77 F/g of specific capacitance, $0.67\Omega$of ESR.

• Korean Chemical Engineering Research
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• v.43 no.3
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• pp.432-437
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• 2005

An electric swing adsorption (ESA) process for recovering highly pure $CO_2$ from the mixed gases was tested. In this study, activated carbon fibers were used as an adsorbent. The activated carbon fibers showed fast adsorption rate and the high adsorption capacity for $CO_2$ adsorption under the condition of the ambient pressure. Activated carbon fiber with higher specific surface area was suitable to repeated adsorption-desorption cycle process, showing consistent breakthrough curve. Especially, the regeneration method by vacuum combined with ESA improved the performance of desorption process by an additional 17％ regeneration efficiency compared to a vacuum only method, and showed the high regeneration efficiency at comparatively low 7-8 Wh energy.

• Microbiology and Biotechnology Letters
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• v.23 no.6
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• pp.702-709
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• 1995

Degradation Of $\kappa $-carrageenan-based film by microorganisms screened from carrageenan source and activated sludge of a carrageenan producing factory was investigated by measuring changes of pH, viscosity, total sugar and total organic carbon (TOC) of the medium containing $\kappa $-carrageenan as a carbon source. Initially fifteen strains of microorganism were isolated from carrageenan source and activated sludge and then three organisms among them were selected based on the ability of growing in the medium including 0.3% $\kappa $-carrageenan as a sole carbon source. They were identified as Escherichia coli, Saccharomyces cerevisiae and Aspergillus niger. As indices of biodegradability Of $\kappa $-carrageenan based film, the changes of pH, viscosity, total sugar, and TOC of the carrageenan film-based medium were tested by the cultivation of single or mixed strains of the identified organisms. Mixed culture showed the highest biodegradability, which resulted in the changes of pH from 6.5 to 3.0, viscosity from 164 cps to 15.6 cps, total sugar content from 2.35 g/l to 0.53 g/l and TOC from 5721 ppm to 232 ppm after 30 days of cultivation. The biodegradability determined as the reduction rate of TOC by pure cultures of Asp. niger, E. coli, Sacch. cerevisiae and mixed culture of the three organisms were 94%, 86%, 80% and 96%, respectively.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.4
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• pp.455-469
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• 2008

VOCs (Volatile organic compounds) are known as one of the harmful chemicals, causing cancer and global warming. Therefore, the proper control, removal, and reduction of the emission of VOCs are important tasks for the environmental protection. Among the method of VOCs removal activated carbon bed is the most efficient and economical method. In this study, the adsorption performance of toluene gas was investigated using various activated carbons. To find out the adsorption efficiency, the H/D (Height/Diameter) of the activated carbon and GHSV (Gas Hourly Space Velocity) of the toluene gas were manipulated with various conditions. The effect of the temperature, humidity and toluene-MEK-IPA mixed gas on adsorption were also investigated. As a result, a high adsorption performance was found when GHSV is lower at room temperature and low humidity. It was also found that the adsorption efficiency of toluene-MEK-IPA mixed gas system was lower than that of toluene gas system.

• Journal of Environmental Science International
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• v.16 no.10
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• pp.1197-1202
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• 2007

Adsorption experiments of binary mixed gases composed of acetone/methylethylketone (MEK), MEK/benzene, MEK/toluene, and benzene/toluene were carried out on activated carbon fixed-bed. The variations of equilibrium adsorption capacity according to type and fraction of binary gas were investigated. In case of binary gases composed of acetone/MEK and benzene/toluene, equilibrium adsorption capacities of MEK and toluene were increased according to the increase of fraction of MEK and toluene, but equilibrium adsorption capacities of acetone and benzene were decreased. In case of binary gases composed of MEK/benzene and MEK/toluene, equilibrium adsorption capacities of benzene and toluene were increased according to the increase of fraction of benzene and toluene, but equilibrium adsorption capacities of MEK was decreased.

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.569-573
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• 2013

In this study, activated carbon fabric was prepared from a cellulose-based polymer (viscose rayon) via a combination of physical and chemical activation (mixed activation) processes by means of $CO_2$ as a gasifying agent and surface and adsorption properties were evaluated. Experiments were performed to investigate the consequence of activation temperature (750, 800, 850 and $925^{\circ}C$), activation time (15, 30, 45 and 60 minutes) and $CO_2$ flow rate (100, 200, 300 and 400 mL/min) on the surface and adsorption properties of ACF. The nitrogen adsorption isotherm at 77 K was measured and used for the determination of surface area, total pore volume, micropore volume, mesopore volume and pore size distribution using BET, t-plot, DR, BJH and DFT methods, respectively. It was observed that BET surface area and TPV increase with rising activation temperature and time due to the formation of new pores and the alteration of micropores into mesopores. It was also found that activation temperature dominantly affects the surface properties of ACF. The adsorption of iodine and $CCl_4$ onto ACF was investigated and both were found to correlate with surface area.