• Geotechnical Engineering
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• v.13 no.4
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• pp.75-84
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• 1997

In this paper, the retardation capacity of marine clay and weathered soil of seashore waste landfill is analyzed by using a laboratory column apparatus for organic and inorganic components which can represent the components of the leachate of municipal waste landfill. The results show that sorption capacity marine clay for potassium is larger than that of weathered soil. Lead and cadmium are adsorbed completely at concentrations higher than the real concentrations developed in the landfill. The bottom soils of seashore landfill can also retard some nondegradable components of organics although their sorption capacities for organics were less than those for inorganics.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.10
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• pp.1747-1756
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• 2000

Crab shell particles (Protunus trituberculatus) and activated carbon (Norit 0.8 SUPRA) were used as packing material in a fixed-bed column. When 1 g crab shell was added in the column packed with 10 g activated carbon. breakthrough to influent 10 mg Pb/L occurred at 1520 bed volumes. as compared to 380 bed volumes for 10 g activated carbon only. Addition of crab shell particles into activated carbon column resulted in increased uptake of lead. The dramatic improvement might be attributed to an increase in $co_3{^{2-}}$ and $OH^-$ available for the binding of lead. From the result of analyses, the major mechanism of lead removal was based on dissolution of $CaCO_3$ in the crab shell followed by precipitation of $Pb_3(CO_3)_2(OH)_{2(s)}$ on the surface of activated carbon. The lead uptake increased two fold as the influent lead concentration was increased from 10 to 50 mg/L. However, it decreased by 40% as the influent pH was lowered from 5.0 to 3.0.

• Korean Journal of Environmental Agriculture
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• v.28 no.1
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• pp.69-74
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• 2009

In Korea, large amounts of chestnut shell as by-products are produced from food industries. However, most of the by-products exist with no disposal options. Biosorption uses biomass that are either abundant or wastes from industrial operations to remove toxic metals from water. Objective of this research was to evaluate the feasibility of using chestnut shell as by-products for removal of metal ions(Pb, Cu and Cd) from aqueous solution. The chestnut shell was tested for its efficiency for metal removal by adopting batch-type adsorption experiments. The adsorption selectivity of chestnut shell for metals was Pb > Cu > Cd at solution pH 5.5. The Langmuir isotherm adequately described the adsorption of chestnut shell for each metal. Using The maximum adsorption capacity predicted using Langmuir equation was 31.25 mg $g^{-1}$ 7.87 mg $g^{-1}$ and 6.85 mg $g^{-1}$ for Pb, Cu and Cd, respectively. Surface morphology, functional group and existence of metals on chestnut shell surface was confirmed by FT-IR, SEM and EDX analysis. The chestnut shell showed an outstanding removal capability for Pb compared to various adsorbents reported in the literatures. The overall results suggested that chestnut shell might can be used for biosorption of Pb from industrial wastewater.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.247-252
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• 2006

오염 퇴적물내 중금속의 방출과 이에 따른 생이용성(bioavalability)은 기존의 가역 평형관계로써 설명하기에 불충분한 것으로 알려져 있다. 최근 연구결과에 의하면 이러한 탈착 저항성을 설명하기 위한 비가역적 모델에 의해 퇴적물내 중금속의 탈착저항성 부분이 존재함이 밝혀졌다. 탈착저항성에 대해서는 아직 충분한 규명이 이루어지지 않았으나, 오염물질의 노화(aging)에 의해 일단 탈착저항성을 띠게 되면 생이용성(bioavailability)이 감소되는 것으로 알려져 있다. 본 연구에서는 노화(aging)가 연안 퇴적물 내 납과 카드뮴의 흡/탈착 특성에 미치는 영향을 알아보기 위해 연속 탈착실험과 biphasic 탈착모델을 적용함으로써 납과 카드뮴의 탈착저항성을 규명하고자 하였다. 그리고 연속 추출 실험을 통해서 노화(aging)에 따른 퇴적물 내 납과 카드뮴의 흡착 기작을 규명하고자 하였다. 연속탈착 실험 결과 시간이 경과함에 따라 탈착저항성부분의 크기가 증가하였으며, 연속추출 실험 결과 납의 경우 carbonate fraction에서 추출된 납이 가장 많았으며, 노화(aging) 따라 exchangeable fraction에서 추출된 납이 감소하는 반면 reducible, organic material, residual fraction에서 추출된 납의 양이 증가하였다. 카드뮴의 경우 가장 많은 양이 추출된 단계는 exchangeable fraction이였으며, organic material fraction에서는 카드뮴이 추출되지 않았다. 노화(aging) 따라 reducible fraction과 residual fraction에서의 추출량이 증가하는 경향을 보였으나 그 양은 매우 적은 것으로 나타났으며, 노화(aging)에 따른 exchangeable fraction과 carbonate fraction에서의 추출량은 큰 변화가 없었다. 대해서는 북한지역의 분포상황을 밝혔다.것을 알 수 있었으며, 크롬과 비소의 경우는 초기에 많이 용출되고, 구리의 경우는 꾸준히 용출되는 것을 알 수 있었다. 3년 된 통나무집이 8년 된 통나무집보다. 용출양이 더 컸으며, 이는 CCA성분이 초기에 많이 용출된다는 것을 의미한다. 억제 효과를 나타내었고 Hep3B에서는 부탄을 분획물 (1 mg/mL)에서 82%의 비교적 높은 성장억제효과를 나타내었다.as a "front" and "back". Thus, Germany′s private space may face a genuine public space and street, which is rare in the Korean housing. Although the layout of indoor space in the korean housing tends to be open, such an openness may be outstanding in living and dining spaces, kitchen and various accesses to rooms. In the case of Germany, such indoor spaces are usually closed to each other. Thus corridors act to separate these spaces. Such differences are analysed to be due to the different perceptions of interpersonal and socio-cultural attributes as intra-family and inter-neighbor relationships or communications. 알 수 있었다.도 질소와 인산처럼 토양지지대가 있는 경우가 낮은 함량을 유지하였다.pe from the daily life, to fantasize and daydre

• Applied Chemistry for Engineering
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• v.20 no.2
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• pp.165-171
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• 2009

Resins were synthesized by mixing 1-aza-15-crown-5 macrocyclic ligand attached to styrene (2th petroleum in 4th class hazardous materials) and divinylbenzene (DVB) copolymer with crosslinkage of 1%, 2%, 8%, and 16% by substitution reaction. The characteristic of these resins was confirmed by content of chlorine, element analysis, thermogravimetric analysis (TGA), surface area (BET), and IR-spectroscopy. The effects of pH, time, dielectric constant of solvent and crosslinkage on adsorption of metal ion by the synthetic resin adsorbent were investigated. The metal ion showed a fast adsorption on the resins above pH 3. The optimum equilibrium time for adsorption of metallic ions was about two hours. The adsorption selectivity determined in ethanol was in an increasing order of uranium $(UO_2^{2+})$ > lead $(Pb^{2+})$ > chromium $(Cr^{3+})$ ion. The adsorption was in the order of 1%, 2%, 8%, and 16% crosslinkage resin and adsorption of resin decreased in proportion to the order of dielectric constant of solvents.

• Journal of the Korean Geotechnical Society
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• v.17 no.2
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• pp.143-150
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• 2001

최근 국내에서는 건설재료의 부족으로 건설부산물인 폐콘크리트를 새로운 토목재료로써 재활용 또는 자원화에 노력하고 있다. 이러한 차원에서 폐콘크리트의 재활용 및 자원화는 사용용도에 적합한 공학적 특성뿐만 아니라 환경적 특성을 분석하여 대상재료의 환경 안정성을 파악해야 한다. 따라서, 본 논문은 폐콘크리트에 대하여 pH시험, 용출시험, 중금속 흡착특성 등 일련의 환경특성 실험을 실시하여 폐콘크리트 사용에 따른 주변 환경에 미치는 영향을 분석하였다. 실험결과, 폐콘크리트의 pH는 11~12정도이고, 폐기물공정시험법과 TCLP법에 의한 용출시험은 법적기준에 모두 만족하는 것으로 나타났다. 또한 중금속 흡착시험은 폐콘크리트나 구리, 납, 카드늄의 제거능이 큰 것으로 나타났으나 반면, 크롬에 대해서는 제거율이 50%정도로 나타났다.

• Resources Recycling
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• v.10 no.4
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• pp.10-17
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• 2001

The present work investigates the possible use of fly ash for the removal of heavy metal ions from aqueous solutions. Batch experiments were conducted and the influences of metal concentration, pH, and fly ash concentration were investigated. Heavy metals used in these studies were lead and zinc. Adsorption studies were done over a range of pH values (3~10) at $25^{\circ}C$ and heavy metal concentrations of 10~400 mg/L using fly ash concentrations of 10 and 20 g/L. Experiments were also conducted without fly ash to determine the extent of heavy metal removal by precipitation. Kinetic and equilibrium experiments were performed and adsorption data were correlated with both Langmuir and Freundlich adsorption models. The results of these studies indicate that 리y ash can be used as an adsorbent for heavy metals in the aqueous solutions, yet the degree of removal depends on the pH.

• Journal of the Korea Organic Resources Recycling Association
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• v.26 no.2
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• pp.33-41
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• 2018

Large amounts of leaves from street trees fall onto the streets annually and need to be cleaned and treated. Cherry trees are common street trees in Korea. The adsorption characteristics of Pb(II) by cherry leaf (CL) and cherry leaf-derived biochar (CB) were studied through a series of batch experiments. CB was produced through the carbonization of CL at $800^{\circ}C$ for 90 min. Carbonization increased the C content and pH value, while decreased H and O contents. Well developed pore structure was observed at the surface of CB. The pseudo-second order model better described the kinetics of Pb(II) adsorption onto CL and CB, indicating that the rate-limiting step of the heavy metal sorption is chemical sorption. Fast adsorption rates and high adsorption capacities were obtained by the carbonization from CL to CB. Langmuir models better adequately described the Pb(II) adsorption onto CL and CB. Maximum adsorption capacities of Pb(II) expressed by Langmuir constant, $Q^0$ were 37.31 mg/g and 94.34 mg/g, when CL and CB were used as adsorbents, respectively.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.277-280
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• 2000

Annually a greate many of mineral demolition wastes consisting mainly of concrete and bricks, is produced in Korea. Waste concrete present a significant potential as construction material. Therefor a series of test was peformed on waste concrete to evaluate adsorption for Cu and Pb.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2018.10a
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• pp.261-261
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• 2018