• 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.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.5
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• pp.515-520
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• 2007

Recently, the treat of sludge is usually progressed by ocean disposal. But it will be totally banned by content of its heavy metal according to London Dumping Convention, gradually. The stable way of treat of sewage sludge should be examined urgently. To solve the problem, recently, there are efficient and environment-oriented method. One of them is to produce absorbent through the activation. This study produces absorbent through steam activation. As basic experiment, optimum activation condition for preparation of good absorbent is researched through study of the fellowing variables : steam flow rate, activated temperature, activation time. As the result of this with standard on iodine adsorptivity, it is chosen, that steam flow rate "30 mL/hr", activation temperature $"500^{\circ}C"$, activation time "60 minutes". At the time, iodine adsorptivity and yield shown that 228.4 mg/g, 77.23%. And also, by using nitrogen adsorption, SEM and EDS are confirmed that pore development, specific surface area, mean pore size, chemical component and content. Pore developed by steam activation is also confirmed that it is micropore.

• Journal of the Korean GEO-environmental Society
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• v.9 no.3
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• pp.45-50
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• 2008

In this work, stainless steel mesh-supported activated carbons were prepared using phenolic resin and cellulose fiber. $ZnCl_2$ was used as a activation reagent in this work. $ZnCl_2$-chemical activation method has been proposed to produce highly porous activated carbons. The objectives of this work were to develop an optimal condition for manufacturing activated carbon assemblies screen from stainless steel mesh and phenolic resin. The iodine number was more increased over activation temperature of $450^{\circ}C$. Iodine number was 657 mg/g at activation temperature of $550^{\circ}C$, penolic resin concentration 20% and $ZnCl_2$ concentration 15%. Iodine number was 1359.4 mg/g when 10% cellulose added to these conditions.

• Applied Chemistry for Engineering
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• v.28 no.6
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• pp.649-654
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• 2017

An activated carbon was prepared from waste citrus peel produced in large amounts in Jeju Island, Korea, using KOH activation and its characteristics was examined. Under the condition of the KOH ratio between 100 and 300%, activation temperature from 400 to $900^{\circ}C$ and activation time from 0.5 to 1.5 h, the iodine adsorptivity of the activated carbon prepared increased but the yield decreased with respect to the increase of each conditions. The iodine adsorptivity and yield of the activated carbon prepared at the activation time of more than 1.5 h were similar to those of using 1.5 h. In addition, as the KOH ratio increased, the specific surface area and pore volume of the activated carbon increased, but the pore diameter decreased. The activated carbon has an average pore diameter of $20{\sim}25{\AA}$. Also, the activated carbon prepared at 300% KOH and $900^{\circ}C$ for 1.5 h has the highest specific surface area of $1,527m^2/g$ and iodine adsorptivity of 1,246 mg/g.

• Journal of the Mineralogical Society of Korea
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• v.22 no.1
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• pp.23-34
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• 2009

The adsorption of iodide on untreated bentonite and bentonites modified with organic cation (i.e., hexadecylpyridinium chloride monohydrate ($HDP^+$)) was investigated, and the organobentonites were characterized using uptake measurements, ${\mu}$-XRD, and electrophoretic mobilities measurement. Uptake measurements indicate that bentonite has a high affinity for $HDP^+$. Our ${\mu}$-XRD study indicates that organobentonites significantly expanded in basal spacing and organic cations were substantially intercalated into the interlayer spaces of bentonite. The electrophoretic mobility indicates that organobentonite tht is modified with organic cations in excess of the CEC of bentonite is completely different from untreated bentonite in the surface charge distribution. We found significant differences in adsorption capacities of iodide depending on the bentonite properties as follows: iodide adsorption capacities were 439 mmol/kg for the bentonite modified with $HDP^+$ at an equivalent amount corresponding to 200% of the CEC of bentonite whereas no adsorption of iodide was observed for the untreated bentonite. The molecular environments of iodine adsorbed on organobentonites were further studied using I K-edge and $L_{III}$-edge x-ray absorption spectroscopy (XAS). The X-ray absorption near-edge structure (XANES) of iodine spectra from organobentonites was similar to that of KI reference solution. Linear combination fitting of EXAFS data suggests the fraction of iodine reacted with the organic compound increased with increasing loading of the organic compound on organobentonites. In this study, we observed significant differences in the adsorption environments of iodide depending on the modified property of bentonite and suggest that an organobentonite has potential as reactive barrier material around a nuclear waste repository containing anionic radioactive iodide.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2006.11a
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• pp.525-528
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• 2006

감귤박을 원료로 하여 활성화제인 KOH를 사용한 약품활성화공정을 수행하여 감귤박-활성탄을 제조하고, 흡착능 및 세공분포 등을 분석한 결과 요오드 흡착능이 KS 규격 중 1급(활성탄 1,100 mg/g 이상)보다 높은 값으로 나타나 양질의 활성탄을 제조할 수 있음을 보였다. 또한 약품활성화법을 사용함으로써 탄화공정에서 제조된 탄화시료보다 월등히 높은 비표면적과 미세세공의 발달이 이루어져 KOH를 이용한 약품활성화법이 활성탄의 제조공정으로서 활용할 수 있음을 확인할 수 있었다.

• Journal of the Korean Society of Groundwater Environment
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• v.4 no.2
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• pp.78-84
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• 1997

Batch and column tests were performed to investigate the sorption capacity of bottom soils of Kimpo metropolitan waste landfill. Sorption capacity and sorption isotherm from the batch test for inorganic and heavy metal substances and retardation capacity of heavy metals from the column test are obtained. It was recognized from the tests that the samples match well with Freundlich isotherm and marine clay has good sorption capacity for potassium and heavy metals such as lead and cadmium. The soil samples with different geologic origins did not show significant differences in the sorption capacity of tested components.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2006.11a
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• pp.521-524
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• 2006

본 연구에서는 농업폐기물인 감귤박의 효율적인 재활용 방안으로 고부가가치 제품인 활성탄을 제조하여 이용하는 가능성에 대하여 조사한 결과, 감귤박 폐액으로부터 건조한 시료의 조성은 대부분이 탄수화물로 구성되어 있으며, 또한 이는 미생물, 농약 및 중금속에 오염되지 않은 순수한 천연 재료로 구성되어 있음을 알 수 있었다. 또한 탄화공정 및 활성화공정을 통해 제조된 활성탄의 요오드 흡착능이 KS 규격 중 1급(활성탄 1,100 mg/g 이상)보다 높은 값으로 나타나 공업용 활성탄으로의 활용이 가능할 것으로 사료된다.

• Clean Technology
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• v.29 no.4
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• pp.272-278
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• 2023

There is a lot of interest in methods for pollutants using adsorption, and recent research is being conducted to show that biochar can be used to remove organic and inorganic pollutants. In particular, wood waste as waste biomass requires a biomass recycling method, and a method to increase the adsorption capacity of biochar produced using wood waste is needed. Biochar is created by Hydrothermal carbonization (HTC) using, which uses low temperature and high pressure, has low energy consumption and does not require moisture removal pretreatment, and biochar is created through chemical activation using KOH, NaOH, and ZnCl₂ chemicals. The adsorption characteristics of biochar were determined by analyzing iodine adsorptivity, specific surface area, pore diameter, pore volume, pore distribution, and SEM according to the activation. The results of analyzing the selecting biochar by activating the biochar produced at HTC 300℃, 4 hr by KOH, NaOH, and ZnCl₂ chemicals, the specific surface area was 774~1.387 m²/g, showing a high specific surface area similar to activated carbon, and it was confirmed that micropores with an average pore diameter in the range of 21~24 Å were formed. As a result of SEM observation, the surface was uniform with a certain shape depending on activation. It was confirmed that one pore was developed and the number of pores increased.

• Korean Chemical Engineering Research
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• v.50 no.4
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• pp.718-722
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• 2012

$H_2S$ adsorption characteristics of adsorbent made by sewage sludge were investigated. For analyses of the manufactured adsorbent, various methods such as Iodine adsorptivity, scanning electron microscope (SEM), and measurements of BET surface area and pore volume were adopted. As the major adsorption characteristic, breakthrough curve was measured by using a continuous fixed bed adsorption column for operating variables such as adsorption temperature ($25{\sim}45^{\circ}C$), aspect ratio (L/D)(3~9), gas flow rate (0.1~2.0 liter/min) and $H_2S$ gas concentration (50~200 ppm). The experimental result showed that the carbonization and activation of sewage sludge are very important for the improvement in $H_2S$ adsorption capacity.