• 제목/요약/키워드: chemical adsorption

검색결과 2,230건 처리시간 0.03초

A Kinetic Consideration on the Selective Adsorption and Molecular Recognition by Molecularly Imprinted Polymer

  • Li, Wuke;Li, Songjun;Luo, Gang;Ding, Kerong
    • Bulletin of the Korean Chemical Society
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    • 제28권8호
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    • pp.1346-1352
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    • 2007
  • This article presents an original work on kinetically studying the selective adsorption and recognition by molecularly imprinted polymer (MIP). With S-naproxen as template, the imprinted polymer was prepared. The result indicates that the prepared polymer shows a more complicated sorption toward S-naproxen than toward its enantiomer R-naproxen. The rate constant in the case of template appears to be a variable. There are also significant deviations from the idealized Langmuir model. Related information indicates that these, in logic, can be a result of biomimic structural and functional complements between imprint and the template, which makes the polymer capable of selectively recognizing the imprint species.

A Study of the Optimum Pore Structure for Mercury Vapor Adsorption

  • Kim, Byung-Joo;Bae, Kyong-Min;Park, Soo-Jin
    • Bulletin of the Korean Chemical Society
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    • 제32권5호
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    • pp.1507-1510
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    • 2011
  • In this study, mercury vapor adsorption behaviors for some kinds of porous materials having various pore structures were investigated. The specific surface area and pore structures were studied by BET and D-R plot methods from $N_2$/77 K adsorption isotherms. It was found that the micropore materials (activated carbons, ACs) showed the highest mercury adsorption capacity. In a comparative study of mesoporous materials (SBA-15 and MCM-41), the adsorption capacity of the SBA-15 was higher than that of MCM-41. From the pore structure analysis, it was found that SBA-15 has a higher micropore fraction compared to MCM-41. This result indicates that the mercury vapor adsorptions can be determined by two factors. The first factor is the specific surface area of the adsorbent, and the second is the micropore fraction when the specific surface areas of the adsorbent are similar.

함침농도와 CO2 가스 유입농도에 따른 활성탄의 흡착특성 (Adsorption Characteristics of Activated Carbons According to Impregnation Concentrations and Inlet CO2 Gas Concentrations)

  • 이동환;감상규;이송우;이민규
    • 한국환경과학회지
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    • 제19권12호
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    • pp.1403-1407
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    • 2010
  • The adsorption characteristics of $CO_2$ gas on impregnated activated carbons with MEA (Mono-ethanolamine) and AMP (2-Amino 2-methyl 1-propanol) were studied to improve the adsorption ability of $CO_2$ gas on activated carbon. The equilibrium adsorption capacity of $CO_2$ gas was increased by increment of impregnation concentration up to 40 %, but decreased above 50 %. The adsorption capacity of activated carbon impregnated with AMP was higher than activated carbon impregnated with MEA. The breakthrough was fast according to increment of inlet concentration of $CO_2$ gas.

개질에 따른 활성탄의 표면특성과 Benzene 증기의 흡착속도 비교 (Comparison of Surface Characteristics and Adsorption Rate of Benzene Vapor According to Modifications of Activated Carbon)

  • 이송우;감상규;이민규
    • 한국환경과학회지
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    • 제17권8호
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    • pp.919-924
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    • 2008
  • The surface properties and adsorption rates of activated carbon modified with acid and base were compared. The distribution ratio of C and C-H on the surface of activated carbon were decreased by modification with acid and base, but the distribution ratio of C-O, C=O, and O=C-O were increased. Base modification damaged the surface of activated carbon more than acid modification, it caused the effect of 6 percent increments of surface area. Adsorption rate model was more suitable to second order equation than first order equation. Adsorption rate was controlled by adsorption in pore better than in surface.

흡착법에 의한 금속이온과 유기산간의 착염 생성계수의 측정법 (Determination of the Formation Constants of Metal Complexes with Organic Acids by Adsorption Method)

  • 제원목
    • 대한화학회지
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    • 제15권4호
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    • pp.199-203
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    • 1971
  • The adsorption method for the determination of the formation constants of the metal complexes with organic acids was developed by using membrane filters. The adsorption method involved the measurements of radioactivities of the adsorbed metal on membrane filters and the filtrate solution after the radioactive metal ion were filtered through membrane filters in the presence of organic ions of varying concentration. Comparing the adsorption method with the ion exchange method, it was seen that the adsorption method was simpler and faster than the ion exchange method. As an example of the metal complex with organic acid yttrium citrate complex was chosen, and the formation constant of the complex obtained by the adsorption method showed $K_f=2.0{\times}10^{-4}(l. mole^{-1})$ at a pH of 7. Also the present study revealed that the carrierfree state of yttrium in aqueous solution was present in the completely ionized state.

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Study on CO Adsorption on in-situ Brass Formed Cu/ZnO

  • Jung, Kwang-Deog;Joo, Oh-Shim
    • Bulletin of the Korean Chemical Society
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    • 제23권12호
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    • pp.1765-1768
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    • 2002
  • The isotherms of CO adsorption on the Cu/ZnO sample treated with with hydrogen and methanol are investigated. The heats of adsorption of CO on the Cu/ZnO treated with hydrogen at 723K for 3 h are in the range from 25.7 kJ/mol at $\theta=0.8$ to 59.8 at $\theta=0.1$, while those on the Cu/ZnO sample treated with methanol at 523 K for 3 h are in the range 30.3 kJ/mol at $\theta=0.8$ to 99.8kJ/mol at $\theta=0.1.$ The Cu/ZnO samples treated with hydrogen do. The heats of adsorption at q=0.1 increase with the methanol treatment time within 30 min and leveled off afterwards.

Remove of Sulphate Ion from Environmental Systems by using AlN Nanotubes

  • Baei, Mohammad T.;Hashemian, Saeedeh;Torabi, Parviz;Hosseini, Farzaneh
    • Bulletin of the Korean Chemical Society
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    • 제35권4호
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    • pp.1139-1143
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    • 2014
  • The adsorption behavior of the sulphate ($SO{_4}^{2-}$) on the external surface of (5,0), (8,0), and (10,0) zigzag AlNNTs was studied by using density functional calculations. Adsorption energies in the nanotubes are about -8.59, -8.04, -8.60 eV with a charge transfer of 0.59, 0.48, 0.56|e| from the sulphate ion to the nanotubes, respectively. The adsorption energies indicated that sulphate ion can be absorbed strongly on the nanotubes. Therefore, these nanotubes can be used for adsorption of sulphate ion from the environmental systems. It was found that diameter of the AlNNTs has slight role in the adsorption of sulphate ion. The electronic properties of the nanotubes showed notable changes upon the adsorption process.

Preparation of Modified Hollow Polypropylene Membrane and Their Adsorption Properties of ${\gamma}$-Globulins

  • Hwang, Taek-Sung;Park, Jin-Won
    • Macromolecular Research
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    • 제11권5호
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    • pp.347-351
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    • 2003
  • The hydrophobic ligand-containing hollow polypropylene (PP) membranes were synthesized by the mutual radiation induced graft copolymerization with glycidylmethacrylate (GMA) onto hollow PP membrane followed by the subsequent functionalization with L-phenylalanine. FT-IR, elemental analysis and UV spectroscopy were utilized to characterize copolymer composition, and degree of grafting, functionalization conversion and ${\gamma}$-globulins adsorption. The degree of grafting on the PP surface increased with the reaction time and total dose of E-beam. In the subsquent functionalization, the amount of L-phenylalanine increased with the increase in the degree of grafting and the degree of conversion was about 30%. The ${\gamma}$-globulins adsorption experiments showed that adsorption capacity had a maximum value at pH 8. The ${\gamma}$-globulins adsorption capacity in the basic pH region was higher than in the acidic pH region.

Stepwise Adsorption in Gas-Solid Adsorption System and Phase Transition in Adsorbed Phase

  • Lee Song Hee;Lee Jo Woong;Pak Hyungsuk;Chang Seihun
    • Bulletin of the Korean Chemical Society
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    • 제3권2호
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    • pp.37-44
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    • 1982
  • In this work we have studied the multilayer stepwise adsorption of gases on solid adsorbents based on the previously developed theory. It is shown that stepwise adsorption isotherms emerge from our theory if an ad hoc adsorption regarding the degree of occupation for each successive layer is abolished and the effect of lateral intermolecular interactions among adsorbate molecules is included. In addition to these the effect of vertical interactions has also been taken into consideration. It seems that the vertical interaction plays a role in deciding the shape and the position of steps in resulting isotherms. It is evident from this research that it is the lateral interaction that is responsible for stepwise adsorption as long as the adsorbent surface is uniform and temperature is sufficiently low.

Heavy-Metal Adsorption Characteristics of Scoria Distributed over the Earth Surface of Jeju Island

  • Soo-Hyoung, Moon;Ho-Won, Lee;Seung-Geon, Kim
    • 공업화학
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    • 제34권1호
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    • pp.86-93
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    • 2023
  • In this study, we investigated the various adsorption factors influencing the adsorption of heavy metal ions based on the study of the composition and physicochemical properties of scoria dispersed throughout Jeju Island. Analysis of the distribution characteristics of scoria samples collected from five areas of Jeju showed that reddish-brown-colored scoria were predominant. Analysis of scoria collected from Jeju Island showed that its mineral components are ordered as follows: SiO2 > Al2O3 > Fe2O3 > CaO and MgO. The experimental data did not show a linear relationship in the pseudo-first-order adsorption kinetics. In contrast, a pseudo-second-order model yielded a positive linear relationship, and this model was subsequently used. It could be concluded based on an intraparticle diffusion model indicating linear relationships that the capture of metal ions on scoria is dominated by the primary adsorption step.