• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2003.10a
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• pp.170-173
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• 2003

Activated Rice-Hull carbon was developed to remove ammonia compounds in water matrix. Isotherm adsorption tests of ammonia were conducted using a bottle-point technique and column test. Residual ammonia after Jar-Test or passing through the column was determined by Indophenol method, and assessed the removal efficiency for ammonia of the adsorbent. As a result, the adsorption capacity for ammonia of activated racehull carbon was very larger than that of coconut shell carbon, because the rice hull carbon had the higher BET surface area of silicate. The activated racehull carbon is under the development as adsorbent to remove ammonia in drinking water and waste water.

• Membrane Journal
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• v.6 no.2
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• pp.109-116
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• 1996

This work is a fundamental study for applying hybrid process coupling adsorption with microfiltration to waste-water treatment. Phenol was separated by adsorption on powdered activated carbon, adsorbed phenol with activated carbon was separated by microfiltration. As the particle size in suspension increased, filtration resistance decreased, and effect of particle concentration on resistance was less pronounced. The rate of uptake was greatly dependent on the degree of phenol loading. For a smaller amounts of activated carbon, the change of permeate concentration before break point and phenol loading with time were steeper than in the case of large amounts. Permeate concentration before break point decreased with decreasing particle size, this could be due to the increase of outer surface of particle and film mass transfer coefficient.

• Korean Chemical Engineering Research
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• v.46 no.2
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• pp.436-442
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• 2008

Organic-inorganic hybrid mesoporous anion-exchange resins were prepared for the adsorption of anions from aqueous solutions. The prepared samples were characterized using nitrogen adsorption-desorption measurements, Fourier transform infrared (FTIR) spectroscopy, and elemental analyses. Batch and kinetic experiments were performed to examine the anion-exchange performances of the prepared samples. Among the prepared samples, the hybrid mesoporous anion-exchange resins functionalized with tributylammonium groups showed higher adsorption capacities for perrhenate ions than did the resin functionalized with trimethylammonium groups. The surfactant, hexadecylamine, which had hydrophobic alkyl chains, also showed affinity for hydrophobic perrhenate anions.

• Korean Journal of Environmental Agriculture
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• v.17 no.1
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• pp.43-47
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• 1998

This study was performed to remove the dissolved benzene in water by using TMA-Zeolite complex which was formed by the adsorption of TMA(Tetramethyl ammonium), a kind of ration surfactant on a natural zeolite produced in Korea. The dorminant clay minerals of the natural zeolite was identified by X-ray diffractometry and Infrared spectrophotometry to be mordenite and clinoptilolite. The CEC of the zeolite used was 95.9 cmol/kg. TMA was adsorbed on natural zeolite very quickly, and the amount of TMA adsorption on zeolite was known to be equivalent to about 8% of the CEC of natrual zeolite. The amount of benzene adsorption on TMA-zeolite complex was much more than natural zeolite, indicating that the dissolved benzene in water could be removed effectively by TMA-zeolite comple.

• Applied Chemistry for Engineering
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• v.23 no.1
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• pp.42-46
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• 2012

In this study, a mesoporous carbon (CMK-3) activated using KOH was applied to the adsorption of formaldehyde, a representative indoor air pollutant. Activation process was carried out by putting KOH-treated CMK-3 in a reactor maintained at $700^{\circ}C$ in $N_2$ atmosphere. The activated sample was characterized using BET, XRD, XPS and FT-IR analysis. The formaldehyde adsorption performance of the mesoporous carbon was improved, which is attributed to the formation of oxygen and nitrogen functional groups on the mesoporous carbon surface by the activation process.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.568-573
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• 2011

Carbon dioxide concentration of railroad passenger cabin is obliged to be kept lower than guideline values of 'Indoor air quality guideline for public transportations', but actual carbon dioxide concentration frequently exceeds this guideline value. Ventilation is most desirable to lower carbon dioxide concentration but there are some cases when the ventilation is not applicable. In this study, carbon dioxide concentration control method using adsorbents was presented. The cation of zeolites were exchanged with various kinds of cations, and the carbon dioxide adsorption performance of the zeolites were studied. The various kinds of cations, solvents, and zeolites were introduced, and it was found that some cation-exchanged zeolites showed good carbon dioxide adsorption performances. It is expected that the obtained results will be used to lower carbon dioxide concentration of railroad passenger cabin.

• Journal of Environmental Science International
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• v.1 no.2
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• pp.167-175
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• 1992

This study was conducted for an efficient utilization of waste fly ash obtained from the power plant. Fly ash was used for synthesizing zeolite. Na-Pl zeolite could be easily synthesized from waste fly ash and showed the potential to remove heavy metal ions. The synthetic zeolite showed good adsorption property for heavy metal much better than raw fly ash and natural zeolites. Na-Pl exhibited the high adsorption efficiency with a maximum value of 260 Pb mg/g and strong affinity for Pb2+ ion. The metal ion selectivity of Na-Pl was determined in a decreasing order : $Pb^{2+}$>$Cd^{2+}$>$Cu^{2+}$+>$Zn^{2+}$>$Fe^{3+}$

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.1 no.2
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• pp.167-175
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• 1997

This study was conducted for an efficient utilization of waste fly ash obtained from the power plant. Fly ash was used for synthesizing zeolite. Na-P1 zeolite could be easily synthesized from waste fly ash and showed the potential to remove heavy metal ions. The synthetic zeolite showed good adsorption property for heavy metal much better than raw fly ash and natural zeolites. Na-P1 exhibited the high adsorption efficiency with a maximum value of 260 Pb mg/g and strong affinity for $Pb^{2+}$ ion. The metal ion selectivity of Na-P1 was determined in a decreasing order : $Pb^{2+}>Cd^{2+}>Cu^{2+}>Zn^{2+}>Fe^{3+}$.

• Resources Recycling
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• v.17 no.5
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• pp.60-65
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• 2008

A study on the removal of silver(Ag) in copper electrolyte was carried out to produce high purity copper by using various method such as ion exchange resin, activated carbon adsorption, copper cementation with powder and wire, CuS precipitation. Parameters, such as reaction time, reaction temperature, addition amount etc. were investigated to determine the effective condition of silver removal. CuS precipitation and ion exchange using Lewatit TP214 was found to be effective. Especially, silver content in copper electrolyte was reduced from 10 ppm to less than 0.1 ppm by ion exchange with Lewatit TP214.

• Journal of Korean Society of Water and Wastewater
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• v.36 no.2
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• pp.121-134
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• 2022

In this study, the removal efficiency of PFCs(perfluorinated compounds) in the GAC(granule activated carbon) process based on the superheated steam automatic regeneration system was investigated in laboratory scale and pilot-scale reactor. Among PFCs, PFHxS(perfluorohexyl sulfonate) was most effectively removed. The removal efficiency of PFCs was found to be closely related to the EBCT, and the removal efficiencies of PFOA(perfluorooctanoic acid), PFOS(perfluorooctyl sulfonate), and PFHxS were 43.7, 75, and 100%, respectively, under the condition of EBCT of 6 min. Afterward, PFOA, PFOS, and PFHxS exhibited the earlier breakthrough time in the order. After that, GAC was regenerated, and the removal efficiency of the PFCs before and after regeneration was compared. As a result, it was shown that the PFCs removal efficiency in the regenerated GAC process were higher, and that of PFOA was improved to 75%. The findings of this study indicate the feasibility of the superheated steam automatic regeneration system for the stable removal of the PFCs, and it was verified that this technology can be applied stably enough even in field conditions.