• Carbon letters
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• v.2 no.1
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• pp.9-14
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• 2001

Adsorption and desorption characteristics of methyl iodide at high temperature conditions up to $250^{\circ}C$ by TEDA-impregnated activated carbon, which is used for radioiodine retention in nuclear facility, was experimentally evaluated. In the range of temperature from $30^{\circ}C$ to $250^{\circ}C$, the adsorption capacity of base activated carbon decreased sharply with increasing temperature but that of TEDA-impregnated activated carbon showed higher value even at high temperature ranges. Especially, the desorption amount of methyl iodide on TEDA-impregnated carbon represented lower value than that on unimpregnated carbon. The breakthrough curves of methyl iodide in the fixed bed packed with base carbon and TEDA-impregnated activated carbon at high temperature were compared. TEDA-impregnated activated carbon would be applicable to adsorption process up to $150^{\circ}C$ for the removal of radioiodine in a nuclear facility.

• Journal of the Korean Applied Science and Technology
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• v.19 no.3
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• pp.213-221
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• 2002

Activated carbons with high surface area of 2,600 $m^{2}/g$ and high pore volume of 1.2 cc/g could be prepared by KOH activation of rice hulls at a KOH:char ratio of 4:1 and $850^{\circ}C$. In order to increase the adsorption capacity of hydrogen sulfide, which is one of the major malodorous component in the waste water treatment process, various contents of $Na_{2}CO_{3}$ and $KIO_{3}$ were impregnated to the rice-hull activated carbon. The impregnated activated carbon with 5 wt.% of $Na_{2}CO_{3}$ showed improved $H_{2}S$ adsorption capacity of 75 mg/g which is twice of that for the activated carbon without impregnation and the impregnated activated carbon with 2.4 wt.% of $KIO_{3}$ showed even higher $H_{2}S$ adsorption capacity of 97 mg/g. The improvement of $H_{2}S$ adsorption capacity by the introduction of those chemicals could be due to the $H_{2}S$ oxidation and chemical reaction with impregnated materials in addition to the physical adsorption of activated carbon.

• 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.

• Carbon letters
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• v.2 no.1
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• pp.37-43
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• 2001

Mercury has been identified as a potential health and environmental hazardous material. Activated carbon adsorption offers promising potential for the control of mercury emissions, and sulfur impregnated (sulfurized) activated carbons has been shown to be an effective sorbent for the removal of vapor phase $Hg{\circ}$ from sources. In this work, vapor phase mercury adsorption by sulfur impregnated activated carbons were investigated. Sulfur impregnated activated carbons were made by variation of impregnation temperature, and the comparison of adsorption characteristics with commercial virgin and sulfurized carbons were made. Factors affecting the adsorption capacity of virgin and sulfurized activated carbons such as pore characteristics, functional groups and sulfur impregnation conditions were discussed. It was found that the sulfur allotropes plays a critical role in adsorption of mercury vapor by sulfurized activated carbons.

• Clean Technology
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• v.23 no.1
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• pp.113-117
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• 2017

We prepared sodium carbonate impregnated activated carbon fiber and evaluated its availability for hydrogen sulfide removal by the comparison with the counterpart, sodium carbonate granular impregnated activated carbon. The sodium carbonate impregnated concentration and immersion duration were chosen as two primary parameters. First, the hydrogen sulfide adsorption capacity increased in proportion to the impregnated concentration up to 3 wt%, above which the sodium carbonate impregnated amount rarely showed an increase due to the pore filling effect for both cases. The optimal impregnated concentration was thus set to 3 wt%. Meanwhile, impregnated activated carbon fiber required only half of the immersion duration compared with granular impregnated activated carbon, while showing a 30% increase on the hydrogen sulfide removal capacity. The greater specific area of impregnated activated carbon fiber explained it. In conclusion, we evaluated advantage of preparation time and improved hydrogen sulfide adsorption capacity by impregnate sodium carbonate, which is capable of reacting with hydrogen sulfide chemically, onto the activated carbon fiber with improved specific area.

• Journal of the Korean Professional Engineers Association
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• v.20 no.3
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• pp.26-29
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• 1987

The physical and chemical characteristics of bacteriostatic water filter media are compared to granular activated carbon upon which a silver impregnated. Silver ion that has been chemically impregnated the activated carbon was the bactericidal agent in water filter media. Also, silver Ion that has teen chemically impregnated onto the activated acetate resin was the bactericidal agent in ultrasonic humidifier. Silver impregnated active carbon and silver cartridge will be able to the bactericidal agents for statical water.

• Applied Chemistry for Engineering
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• v.27 no.1
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• pp.62-67
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• 2016

In this study, a pellet-type adsorbent was prepared by using the water-treatment sludge as a raw material, and its physical and chemical properties were analyzed through $N_2$-adsorption, XRD, XRF, and $NH_3$-TPD measurements. Adsorption performance for gaseous ammonia and formaldehyde was compared between the pellet-type adsorbents prepared from water-treatment sludge and the impregnated activated carbon. Although the surface area and pore volume of the pellet-type adsorbent produced from water-treatment sludge were much smaller than those of the impregnated activated carbon, the pellet-type adsorbent produced from water-treatment sludge could adsorb ammonia gas even more than that of using the impregnated activated carbon. The pellet-type adsorbent prepared from water-treatment sludge showed a superior adsorption capacity for ammonia which can be explained by chemical adsorption ascribed to the higher amount of acid sites on the pellet-type adsorbent prepared from water-treatment sludge. In the case of formaldehyde adsorption, the impregnated activated carbon was far superior to the adsorbent made from the water-treatment sludge, which can be attributed to the increased surface area of the impregnated activated carbon.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.11
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• pp.1011-1016
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• 2010

The $H_2S$ adsorption characteristics and property analyses of granular activated carbon adsorbent impregnated with basic solution such as NaOH, KOH, and $(CH_2CH_2OH)_2NH$ were investigated. The concentrations of NaOH and KOH reagent ranged over 1 to 5 M, The concentration of $(CH_2CH_2OH)_2NH$ was in the range of 0.1 to 1 M. Adsorption temperature($25{\sim}45^{\circ}C$) and adsorbate ($H_2S$) concentration (18.23 mg/L) were applied. The experimental results showed that the BET surface area of activated carbon impregnated with KOH decreases from $1,050\;m^2/g$ to $750\;m^2/g$, and the acidity of activated carbon impregnated with NaOH decreases from 0.541 meq/g-AC to 0 meq/g-AC, as the concentration of basic solution increases, while the pH of impregnated activated carbon increased from 9.54 to 10.94 for three basic solutions. It was also found that the $H_2S$ adsorption equilibrium capacity of activated carbon impregnated with NaOH, KOH, $(CH_2CH_2OH)_2NH$ increased with increasing temperature and $H_2S$ adsorption equilibrium capacity of the activated carbon impregnated with diethanolamine was much higher than other cases. At adsorption temperature of $45^{\circ}C$, the $H_2S$ adsorption equilibrium capacity of impregnated activated carbon was 2.0~3.3 times lager than that of pure activated carbon.

• Journal of Korean Society for Atmospheric Environment
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• v.31 no.2
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• pp.173-180
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• 2015

The purpose of this study was to fabricate a ferric nitrate impregnated activated carbon, and the performance for hydrogen sulfide by adsorption was evaluated. Sodium hydroxide was utilized to control pH in the process during generation of ferric hydroxide on the surface of the carbon. Critical mixing duration for generation of ferric hydroxide on the carbon was 48 hrs at pH 1 of the solution, in which the chemical adsorption of hydrogen sulfide was enhanced. The adsorption capacity of the impregnated carbon increased up to 0.10 g hydrogen sulfide/g carbon, which was 4.3 times higher than that of the raw carbon. Presence of FeOOH on the surface of the impregnated carbon was examined by X-ray diffraction.

• 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.