• Title/Summary/Keyword: 흡착율

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Multi-solute Adsorption of Oranic Compounds in Soil (유기화합물들이 혼합상태에서 토양에 흡착하는 성질에 관한 연구)

  • 윤춘경
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.37 no.2
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    • pp.41-52
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    • 1995
  • 혼합상태에서 유기화합물들이 토양에 흡착하는 성질에 관해서 5개의 유기화합물(페놀,2,4-디크로로페놀, 2,4,6-트리크로로페놀, 부루신, 따이오유리아)과 2종류의 토양을 이용하여 연구하였다. 일반적으로 따이오유리아를 제외하고는 한가지 물질이 혼합상태에 있는 다른물질이에 의 흡착력이에 제약을 받아서 단독으로 있을때 보다 흡착율이 낮았다. 따이오유리아는 단독인 경우보다 혼합상태일 때 더 많은 흡착을 보였는데 이는 혼합상태에서 오히려 흡착이 증가할수도 있음을 나타낸다. 혼합이 흡착에 비치는 영향은 페놀의 혼합상태와 단독상태에서의 흡착상태를 여러가지 형태로 비교하여 검토하였는데 산성이고 유기물질이 많은 토양보다 혼합으로 인한 흡착의 억제 효과가 뚜렷하였다.

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Adsorption of Cadmium Ion by Wood Charcoal Prepared with Red oak (Quercus mongolica) (신갈나무 목탄의 카드뮴(Cd)이온 흡착 특성)

  • Jo, Tae-Su;Lee, Oh-Kyu;Choi, Joon-Weon;Byun, Jae-Kyung
    • Journal of the Korean Wood Science and Technology
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    • v.36 no.3
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    • pp.93-100
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    • 2008
  • For investigation of adsoption properties of cadmium elimination by wood charcoal, $25m{\ell}$ aqueous cadmium solutions in various concentrations were treated with 0.2 g wood charcoal of Red Oak (Quercus mongolica) for 280 minutes. Almost 100% of cadmium elimination ratio was obtained in the solutions with initial concentration of 20 and 40 ppm in the treatment, whereas they were 75 and 50% in those of 80 and 160 ppm. In the effect of treatment time, the highest amount of cadmium ions was eliminated during the first ten minutes in each solution so that the elimination ratio of each case was over 70% of the maximum elimination value. From the analysis of adsorptive cadmium adsorption mechanism using the Langmuir adsorption isotherm, it was suggested that cadmium ion molecules were adsorbed at the active sites on the charcoal particle in form of one layer. The Gibbs free energy of the adsorption process was calculated in negative value for each solution. This means the adsorption processes are spontaneous which do not require the extra input energy.

Physicochemical Adsorption Characteristics of MTBE and Cadmium on Clay Minerals (점토광물에 대한 MTBE와 카드뮴의 물리화학적 흡착 특성)

  • Lim, Nam-Ho;Seo, Hyung-Joon;Kim, Chang-Gyun
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.3
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    • pp.231-239
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    • 2005
  • This study was performed to investigate adsorption characteristics of MTBE and Cd depending upon types of clay minerals md their physicochemical properties. The adsorption characteristics were examined by batch adsorption test on various experimental parameters such as adsorption time, ratio of solution to soil, concentration of contaminants, content of organic matter, pH, and zeta potential. The adsorption efficiency of MTBE or Cd for three types of clays decreased in response to the increase of the ratio of solution to soil whereas their adsorbed amounts increased. MTBE was greatly adsorbed in the decreasing order of vermiculite, bentonite, and CTAB-bentonite while Cd was adsorbed in the decreasing order of bentonite, vermiculite, and CTA-bentonite. An equilibrium isotherm for MTBE was well fitted to Freundlich plotting whereas that for Cd was closely corresponded to Langmuir isotherm. The adsorbed amount of MTBE on bentonite and vermiculite showed the maximum at 1% and 5% of humic acid, thereafter diminished while the adsorbed amount of MTBE on CTAB-bentonite increased in proportion to humic acid. Conversely, the adsorbed amount of Cd on the addition of humic acid continued to increase regardless of types of adsorbents. For all types of adsorbents, adsorbed quantity and adsorption efficiency of Cd have been coincidently increased at pH 8 and they were further enhanced at pH 10 showing 90% adsorption efficiency. Upon pH rose, the zeta potential on each adsorbent began to decrease, while increasing Cd concentration led to decline of zeta potential, which in turn ascribed to lowering dispersion stability that could consequently enhance adsorption capability.

피트휴민(peat-Humin)과 중금속 흡착반응 연구

  • 이창훈;신현상;임동민;강기훈
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2004.04a
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    • pp.135-138
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    • 2004
  • 본 연구는 중금속으로 오염된 폐수처리에 있어 친환경적 유기흡착제로서 휴믹물질의 활용성을 평가하기 위한 기초 연구로서 이탄(peat moss)으로부터 Humin을 분리 한 후, 중금속 이온(Cd(II),Cu(II))과의 흡착특성을 조사하였다. 이탄으로부터 추출한 peat-Humin의 함량은 94%이상을 나타냈으며, 분자의 작용기 특성은 일반 토양 휴믹물질(soil humic substance)과 유사하였다. peat-Humin과 중금속 이온(Cd(II),Cu(II))과의 흡착 반응은 5분내에 빠른 흡착형을 보였으며, pH 5-6에서 가장 높은 중금속 제거율을 보였다. pH 3의 산성조건에서도 50%정도의 제거율을 보였다. pH 5에서의 등온흡착 실험결과를 Freundlich 등온식에 적용하여 해석한 결과, 각의 중금속에 대한 peat-Humin의 흡착상수(Kf)는 Cd(II)이 8.07 그리고 Cu(II)가 4.56으로 나타났다.

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Coadsorptions of Carbon Monoxide and Oxygen on Polycrystalline Nickel Surface (다결정 니켈 표면에서의 CO 와 $O_2$의 공동흡착)

  • Soon Bo Lee;Jin Hyo Boo;Woo Sub Kim;Woon Sun Ahn
    • Journal of the Korean Chemical Society
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    • v.37 no.12
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    • pp.1019-1024
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    • 1993
  • The coadsorption of carbon monoxide and oxygen on polycrystalline nickel surface has been studied using XPS at the room temperaure. The adsorption of CO on the nickel surface precovered partially with oxygen is found to take place by the following steps: The CO molecules react with the preadsorbed oxygen atoms to liberate $CO_2$ gas at the initial stage of low CO exposures, and they are coadsorbed gradually with the increasing CO exposures. The extent of coadsorption at the higher CO exposures is found to decrease with the increasing degree of oxygen preadsorption. This finding is explained in terms of the reduced adsorption site for CO as a consequence of oxygen preadsorption. The CO molecules preadsorbed on the nickel surface inhibited the adsorption of $O_2$ molecules. The increase of oxygen exposure led to the dissociation of preadsorbed CO, and the NiO layers were formed concurrently. The dissociation was rendered to arise from an oxygen-to-CO energy transfer.

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Removal of Cd(II) by Cation Exchange Resin in Differential Bed Reactor (미분층반응기에서 양이온 교환수지에 의한 카드뮴(II)의 제거)

  • Kim, Jong-Tae;Chung, Jaygwan G.
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.7
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    • pp.1193-1203
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    • 2000
  • In this study, in order to remove Cd(II) from aqueous solutions, strongly acidic cation exchange resin(SK1B) by Diaion Co. was employed as an adsorbent. Experiments were mainly performed in two parts at room temperature($25{\pm}5^{\circ}C$) : batch tests and adsorption kinetics tests. In batch tests adsorption equilibrium time, pH effects, temperature effects, several adsorption isotherms, and finally desorption tests were examined. In differential bed tests, an optimum flow rate and an overall adsorption rate were obtained. In the batch experiment, adsorption capability increased with pH and became constant above pH 6 and adsorption quantity increased with temperature. Batch experimental data found that Freundlich and Sips adsorption isotherms were more favorable than Langmuir adsorption isotherm over the range of concentration (5~15ppm). The desorbent used in the desorption test was hydrochloric acid solution with different concentrations(0.01~2N). The degree of regeneration increased with concentration of desorbent and decreased slightly with the number of regeneration. In the continuous flow process using a differential bed reactor, the optimum flow rate was $564m{\ell}/min$ above which the film diffusion resistance was minimized. The overall adsorption rate for the removal of Cd(II) by cation exchange resin was found as follows ; $r=1.3785C_{fc}^{1.2421}-2.0907{\times}10^{0.0746C_i}\;q_e^{0.0121C_i-0.0301}$

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A Study on the Removal Characteristics of Phenol Using Waste CDQ Dust as Adsorbent (폐CDQ 분진을 흡착제로 한 페놀제거특성에 관한 연구)

  • Kim, Jin-Wha;Lee, Jung-Min;Kim, Dong-Su
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.7
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    • pp.1213-1223
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    • 2000
  • The adsorption characteristics of phenol has been studied by using CDQ (Cokes Drying Quenching) dust as an adsorbent. The adsorption capacity of CDQ dust was shown to be 42% about removal for 300 ppm phenol solution at the equilibrium adsorption time of 60 min. Removal percentage of phenol increased as the initial phenol concentration was raised in the experimental conditions and the adsorption behavior was explained well by Freundlich adsorption isotherm. Kinetic study showed that the adsorption followed 1st, 1.5th, and 2nd-order rate equation in the sequence as the adsorption time passed. Since the adsorption amount of phenol was increased as the adsorption temperature was raised, the adsorption was thought to be endothermic, and several thermodynamic parameters have been calculated based upon experimental data. Adsorbed amount of phenol on CDQ dust changed little according to the variation in the solution pH except for the slight decrease under the strong alkaline condition.

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Work Function Change Induced by Oxygen Adsorption on Tungsten Single Crystal Surfaces (산소 흡착에 의한 텅스텐 결정면의 일함수 변화)

  • 박노길;김기석;황정남;최대선
    • Journal of the Korean Vacuum Society
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    • v.2 no.3
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    • pp.319-324
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    • 1993
  • 개끗한 텅스텐 결정면의 일함수와 산소 흡착에 의한 텅스텐 결정면(123), (310), (221)의 일함수의 변화를 장전자 방출법으로 측정하였다. 일함수는 Fowler Nordheim equation을 사용하여 계산하였으며 흡착율을 결정할 수 있는 간단한 방법을 제시하였다.

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Effect of pH on the binding of hGM-CSF to ion exchange resin

  • Myoung, Hyun-Jong;Lee, Sang-Yoon;Lee, Kyoung-Hoon;Han, Kyu-Boem;Kim, Dong-Il
    • 한국생물공학회:학술대회논문집
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    • 2003.10a
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    • pp.320-323
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    • 2003
  • The effects of pH on the binding of human granulocyte-macrophage colony-stimulating factor (hGM-CSF) expressed from transgenic plant cell suspensions to cationic and anionic exchange resins were investigated. In terms of stability, the optimum pH was found to be 5-7. In the case of using buffer exchange, when CM-sepharose was used as a cationic exchange resin, the best binding pH was 4.8 (77%) and when DEAE-sepharose was used as an anionic exchange resin, the best binding pH was 5.5 (74%). Without using buffer exchange, the optimum pH was 4.6 and the adsorption yield was 84%. From these results, a possibility of overcoming the degradation and instability of secreted protein product by in firm adsorption was found.

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Removal of Heavy Metals, Cd(II) and Pb(II) Ions in water by Sargassum Herneri (괭생이 모자반에 의한 수중 중금속 Cd(II), Pb(II) 이온의 제거)

  • Park, Kwang-Ha;Park, Mi-A;Jang, Hoon;Kim, Eun-Kyung;Kim, Young-Ha
    • Analytical Science and Technology
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    • v.12 no.3
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    • pp.196-202
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    • 1999
  • Brown algae, Sargassum horneri, was used as an adsorbent to remove heavy metal Cd(II) and Pb(II) ions. Sargassum horneri picked in East Coast was formulated into the grain with the size of 40-60 mesh after wind dry. Batch method was used in order to investigate the adsorption rate by measuring the adsorption amounts with shaking time. In the column method, the adsorption amounts were measured by flowing metal solutions into the algae-packed column at the rate of 1 ml/min. Adsorption amounts in both batch method and column method were in the following order : pH 10.5>7.0>3.5. It was found that Pb(II) was more adsorbed on the algae grain than Cd(II). It was also revealed that the adsorption amounts reached the maximum within 5 minutes irrespective of pH condition in the batch method. It was concluded that the batch method was more effective than the column method in terms of recovery rate.

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