• 제목/요약/키워드: Sorption

검색결과 1,062건 처리시간 0.057초

지하매질에서의 방사성핵종흡착: 단일광물의 역할 (Radionuclide Sorption in the Geosphere: Role of Single Minerals)

  • Cho, Young-Hwan;Hyun, Sung-Pil;Hahn, Pilsoo
    • 한국광물학회:학술대회논문집
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    • 한국광물학회.한국암석학회 2001년도 공동학술발표회 논문집
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    • pp.40-40
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    • 2001
  • The sorption behavior of Cs(I), Sr(II), and U(VI) on representative single minerals(oxide and clay) and rocks were comparatively studied by using batch type sorption experiment. The effects of pH, ionic strength and the sorption mechanism were also discussed. It was found that mineral structure played as a main factor governing the sorption characteristics of Cs(I), Sr(II). The sorption of Cs(I) and Sr(II) on minerals showed ionic strength-dependency, which is a indirect sign of weak binding between metal cation and mineral surfaces. However, the sorption behavior of U(VI) was quite different compared with that of Cs(I), and Sr(II). Fe-oxide minerals showed strong tendency for U(VI) sorption, dominating the sorption in the composite/mixture systems. The surface characteristics which arise from mineral structure, and the affinity of metal ions to the sorption sites of minerals are the key to understand the role of minerals in the radionuclide sorption.

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비결정 폴리아마이드에 대한 유기화합물의 흡착 특성 연구 (Sorption of Organic Penetrants by Amorphous Polyamide)

  • 이명훈
    • 한국포장학회지
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    • 제4권1호
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    • pp.11-16
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    • 1997
  • Sorption studies involving the sorption of n-propanol by an Amorphous Nylon(Nylon 6I/6T) were carried out as a function of sorbate vapor activity at $23^{\circ}C$. Vapor activity levels from 0.035 to 0.91 were investigated to evaluate the concentration dependency of sorption mechanism. Sorption behavior of propanol by Nylon 6I/6T showed distinctive two mode sorption phenomena as a function of Vapor activity. At Vapor activity levels below a=0.11, equilibrium sorption was achieved within a short period of time(less than 20hrs), which can be interpreted as following a Fickian diffusion model. A Langmuir-Flory-Muggins Dual Mode Sorption model can also be applied at these concentration levels. However, for Vapor activities above a=0.11, the sorption process appeared to be non-Fickian and resulted in a lack of equilibrium being attained.

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천연 고령토의 폐수 중 납 흡착에 관한 연구 (A Study on Adsorption of Lead(II) in Wastewater Using Natural Kaolinite)

  • 이종은
    • 한국환경보건학회지
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    • 제21권3호
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    • pp.77-86
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    • 1995
  • Lead(II) removal efficiency by natural kaolinite was investigated through laboratory experiments. This study was conducted in two phases-sorption and desorption. In the adsorption study, the influence of sorption kinetics and sorption isotherm and various parameters such as pH, temperature, coexisting other heavy metal ions on the lead adsorption was investigated. And desorption study was carried out in order to find the re-usability of kaolinite as an adsorbent. The results of the study are as follows. 1. Sorption kinetics was investigated under the condition of 2.5 mg/l adsorbent concentration, pH 6.5$\pm$0.05, temperature $30\pm 0.5\circ$C, initial lead(II) concentration 25 mg/l. Adsorption rate was initially rapid and the extent of adsorption arrived at adsorption equilibrium with 73% adsorption efficiency in an hour. 2. The sorption isotherm experiment was made with different initial lead(II) concentration. A linearized Freundlich equation was used to fit the acquired experimental data. As a result, Freundlich constants, the sorption intensity (1/n) was 0.47 and the measure of sorption (k) was 2.44. So, it was concluded that sorption of lead(II) by kaolinite is effective. 3. The effect of pH on lead(II) sorption by kaolinite shows that at a pH of 3, only 6% of the total lead(II) was adsorbed and at a pH 9, 97% of the lead(II) was removed. And the effect of temperature on lead(II) sorption by kaolinite shows that as the temperature increased, the amount of lead(II) sorption per unit weight of kaolinite increased. But the effect was minor (p<0.05). 4. Sorption isotherm of lead coexisting cadmium (II) or zinc (II) was lower than that of lead itself. It was caused by the result of competitive sorption to adsorption site. And there was no difference between the sorption isotherm of cadmium and zinc. 5. In desorption studies, only 5.12% desorption took place in distilled water, while 52.08% in 0.1 N hydrochloric acid. Consequently used kaolinite could be regenerated by hydrochoric acid.

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카드뮴, 납, 구리에 대한 슬래그의 흡착특성평가 (Assessment of Sorption Behavior on Slag Against Heavy Metals)

  • 이광헌;최성대;정재식;박준범;남경필
    • 한국지반공학회논문집
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    • 제24권6호
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    • pp.17-25
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    • 2008
  • 폐금속 광산 지역 등지에서 중금속으로 오염된 지하수의 정화 및 오염확산 방지를 위하여 투수성 반응벽체를 사용 할 수 있다. 본 연구에서는 슬래그가 투수성 반응벽체 충진물질로서 적당한지 평가하기 위하여 폐광산 지역에서 문제가 되고 있는 몇 가지 중금속(i.e., Pb, Cu, Cd)에 대한 슬래그의 반응성을 평가하였다. 폐광산 지역 지하수에는 중금속류들이 복합오염의 형태로 존재하며, 음이온 물질인 황산염, 탄산염 등도 공존한다. 중금속으로 오염된 현장의 조건을 고려하여, 1) 중금속 종류에 따른, 2) 초기 농도에 따른, 3) 음이온(황산염)의 존재에 따른 영향을 회분식 실험을 통하여 슬래그의 흡착능을 평가하였다. 슬래그의 흡착특성은 등온흡착평형(equilibrium sorption)과 동적인 흡착(kinetic sorption)인 경우 각 조건에 따른 영향을 확인하였다.

환경 추적자의 흡착 특성을 이용한 수리지화학적 활용 가능성 고찰 (Potential Application of Environmental Tracer in Hydrogeochemistry Using Sorption Properties)

  • 정성욱;장세은;김민경;김성표;엄우용
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제17권6호
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    • pp.59-68
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    • 2012
  • This study provided sorption properties of chlorofluorocarbons (CFCs), and elucidated potential application of CFC sorption data in hydrogeochemistry. Prior sorption studies were reviewed for hydrophobic organic compounds similar to the CFCs, because there were only few CFC sorption studies. The CFCs are regarded as relatively conservative chemicals in groundwater environments based on their moderate hydrophobicity. However, thermally altered carbonaceous matter (TACM) can significantly increase sorption capacity and nonlinearity for hydrophobic organic compounds such as CFCs, compared to general soil organic matter. CFC sorption behavior are close to the sorption for reviewed organic chemicals. Therefore, the CFC sorption data can be used for determining hydrogeochemical properties and predicting transport of organic contaminants in TACM-containing aquifer environments.

Sorption Isotherms and KocS Estimation of Pyrethroids in Sediments

  • Lee, Sang-Jin;Shin, Hyun-Moo
    • 한국환경과학회지
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    • 제12권11호
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    • pp.1173-1179
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    • 2003
  • Laboratory sorption isotherm batch studies have been attempted to elucidate interaction of synthetic pyrethroids (bifenthrin and permethrin) with sediments and their fractions. As a nonlinear isothermal model, the Freundlich equation was applied to sorption results obtained from sediments to investigate the relationship between synthetic pyrethroids and sediments containing different amounts of organic carbon. Results demonstrated that the sorption capabilities of bifenthrin and cis- and trans-permethrin was in the order of bifenthrin, cis-permethrin and trans-permethrin, respectively, indicating that adsorbed bifenthrin was the most stable followed by cis- and trans-permethrin in all sediments. Their sorption capability was closely related to organic carbon contents in sediments. Higher sorption was observed in sediments containing higher organic carbon contents. Sorption study extended into the fractions, clay and humic acids, extracted from a sediment, indicated that higher sorption capacity in humic acids occurred than in the clay of both examined bifenthrin and permethrin. This study demonstrates the sorption of synthetic pyrethroids with sediments, and will help in the understanding of the transport and fate of synthetic pyrethroids existing in field sediments.

벽지의 흡.방습 특성에 따른 항곰팡이 성능 평가 (Evaluation of Antifungal Performance of Wallpapers According to Sorption Properties)

  • 문현준;김경민;유승호
    • 대한건축학회논문집:계획계
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    • 제29권7호
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    • pp.247-254
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    • 2013
  • The hygric properties of building materials are related to condensation phenomena and biological contaminants such as fungi infestations, especially in building environments. If the relationship between mould growth and hygric properties is identified and the appropriate building materials are used indoor, it can protect indoor environment from infection of mould. The purpose of this study is to find the relationships between sorption properties and mould germination/growth on wallpapers. An experimental study was conducted to characterize the sorption properties of the selected wallpapers. The sorption properties of the selected wallpapers were obtained at various relative humidity conditions. Then, the selected wallpapers were inoculated with three fungi species and mould germination/growth rates were observed. The correlations between sorption properties and mould germination/growth rate were analyzed. The results showed that the wallpapers that had high sorption properties, which resulted in higher antifungal performance compared to the wallpapers with lower sorption properties.

흡습 냉각 패드에서의 열 및 물질전달에 관한 연구 (Theoretical Analysis on the Heat and Mass Transfer in a Sorption Cool Pad)

  • 황용신;이대영;박봉철
    • 설비공학논문집
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    • 제16권2호
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    • pp.167-174
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    • 2004
  • A sorption cool pad brings cooling effect without any pre-cooling, nor any external energy supply. It uses evaporative cooling effect stimulated by the desiccative sorption. In this paper, heat and mass transfer in the sorption cool pad are investigated theoretically. The evaporative cooling process caused by the desiccant is modeled and analyzed considering the sorption characteristics of the desiccant. Two nondimensional parameters are found to dominate the cooling process: one is related to the psychrometric characteristics and the other is to the sorption capacity of the desiccant. The former decides the time to reach the lowest temperature and the later controls the time duration of the cooling effect being sustained.

Mechanisms of Cu(II) Sorption at Several Mineral/Water Interfaces: An EPR Study

  • Cho, Young-Hwan;Hyun, Sung-Pil;Pilsoo Hahn
    • 한국자기공명학회:학술대회논문집
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    • 한국자기공명학회 2002년도 International Symposium on Magnetic Resonance
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    • pp.72-72
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    • 2002
  • In most traditional sorption study in environmental conditions, experimental sorption data have been measured and interpreted by empirical ways such as partition coefficient and sorption isotherms. A mechanistic understanding of heavy metal interactions with various minerals (metal oxides, clay minerals) in aqueous medium is required to describe the behavior of radioactive metal ions in the environment. Various spectroscopic methods provide direct or indirect information on sorption mechanisms involved. We applied EPR (Electron Paramagnetic Resonance) spectroscopy to investigate the nature of metal ion sorption at water/mineral interfaces using Cu(II) as a spin probe. The major sorbed species and their motional state was identified by their EPR spectra. They showed distinct signals due to their strength of binding, local structure and motional state. The EPR results together with macroscopic sorption data show that sorption involved at least three different mechanisms depending on chemical environments (1).

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Effects of solution, sorbate, and sorbent chemistries on polycyclic aromatic hydrocarbon sorption to hydrated mineral surfaces

  • Yim, Soobin
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2003년도 추계학술발표회
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    • pp.132-135
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    • 2003
  • Solution chemistry, sorbate chemistry, and sorbent chemistry were widely investigated to find important factors that affect PAH sorption on mineral surfaces and to elucidate its microscopic mechanism. The solution chemistry, pH and ionic strength caused measurable change of HOC sorption reaction to minerals. The detectable change of Ka occurred at a pH region crossing the PZC (Point of Zero Charge) of each mineral. The PAH hydrophobicity, one of sorbate chemistry, was observed to have a strong correlation with PAM sorption to mineral. Mineral surface area was not found to be a predominant factor controlling PAH sorption. The mineral type might be more likely to play a crucial role in controlling the PAH sorption behavior. The CEC (Cation Exchange Capacity) of mineral, representing surface charge density, has meaningful correlation with regression slope of sorption coefficients (log $K_{d}$) versus aqueous activity coefficients (log Υ$_{w}$).).).

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