• Journal of Korean Society of Environmental Engineers
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• v.39 no.1
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• pp.19-25
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• 2017

In this study, a electrostatic filter which could be applicable to road environment was developed and evaluated in adsorption capacity. The evaluation were performance for removal by particle size and adsorption amount by pressure using ASERAE 52.1 and 52.2. The range of size for removal test was $0.3{\mu}m{\sim}10.0{\mu}m$ which had 12 steps. The filter showed 91.3% removal efficiency from $2.5{\mu}m$ and under the size, average 53.5% proportional to decreasing size value. The weight removal was 96.7% from 22.6 mmaq, initial pressure to 35 mmaq, end pressure with $715.9g/m^2$, the adsorption amount. The shape of isotherm was expressed as Langmuir's one. After washing saturated filter with dust to end pressure, the initial pressure and adsorption amount of the filter showed a light drop with no removal efficiency decline.

• Journal of the Mineralogical Society of Korea
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• v.21 no.1
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• pp.45-56
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• 2008

This study was carried out to determine the effects of mineral composition and grain size of zeolite and bentonite from Po-hang and Kyung-ju, South Korea on the adsorption of heavy metals. Zeolite specimen consists mainly of mordenite, clinoptilolite, heulandite etc. And bentonite specimen is mainly composed of montmorillonite. Five heavy metals, Cd, Cr, Cu, Mn, and Pb were used to conduct the relevant adsorption experiments with the fixed concentrations of 10 ppm and 20 ppm, respectively. Host specimens excluding specimen for Cr resulted in the adsorption rate over average 80 percent, and over 95 percent for Pb. This study indicates that zeolite is more efficient in the adsorption of the heavy metals than bentonite, and its adsorption rate tends to decrease with increasing concentration of the heavy metals.

• Applied Chemistry for Engineering
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• v.9 no.4
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• pp.574-578
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• 1998

Electrochemical Ion Exchang(EIX) electrode containing Amberlite IRP-64 as a cation ion exchange resin and Stylene-Buthylene-Rubber(SBR) as a binder was fabricated by the compressed diecasting method. The adsorption and elution characteristics in copper sulfate solution were investigated at the various electrode potentials and electrolyte pHs. In the adsorption process, it was found that the maximum adsorption rate of copper was obtained at -1800 mV and the ratio of adsorption was 92% during 90 min. In the elution process, the elution rate of copper was increased in proportion to anodic potential in the present experimental range and the ratio of elution was 88% during 50 mins at 3600 mV. The adsorption and elution processes were significantly affected by the variation of local pH in the vicinity of electrochemical ion exchange electrode. The higher performances of adsorption and elution were elution were obtained at basic and acidic eletrolytes.

• Journal of the Korean Vacuum Society
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• v.4 no.2
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• pp.142-149
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• 1995

본 연구에서는 새로운 장전자 방출법(DOFEC법)으로 W(210)면의 수소 흡착에 의한 일함수의 변화, heat of desorption에 대하여 연구하였다. 텅스텐(210)면에 수소가 흡착될 때 흡착율에 따라 일함수가 증가하다가 다시 감소하는데 이것은 수소가 처음에는(210)면의 step((100)면)에 흡착되고 dose를 증가시킴에 따라 terrace((110)면)에 흡착되기 때문임을 알았다. 즉, terrace보다 step의 sticking coefficient가 더 크며 zero coverage에서의 그 비는 2.57이며 이는 타 연구 결과와 잘 일치한다. (210)면의 step과 terrace의 수소 흡착에 대한 일함수의 정량적인 변화량 그리고 수소 dose량에 대한 각각의 면에 대한 상대적인 흡착율을 얻었으며, 이 결과는 독립된(110)면 또는 (100)면의 결과와 잘 일치됨을 알았다. 또한 이 결과는 흡착 실험에 있어서 dose량을 흡착률로 환산하는데 사용될 수 있다. 텅스텐(210)면에는 4개의 흡착 site가 존재하며 이 site들 중 $\beta$2과 $\beta$4 state는 second order 탈착 과정을 따르며 $\beta$1과 $\beta$3 state는 first order 탈착과정을 따른다. 따라서 텅스텐(210)면에는 수소가 해리적 흡착을 함과 동시에 비해리적 흡착도 함을 알았으며(210)면의 각 흡착 site를 이에 대응되는 (100)면과 (110)면의 흡착 site와 비교 검토하였다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.5
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• pp.473-477
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• 2001

Chitosan has been used as an effective adsorbant for the treatment of wastewater from seafood processing. We investigated the effects of deacetylation degree (DD) and molecular weight (MW) of chitosan on protein adsorption ability and also the optimum conditions of chitosan treatment for protein adsorption in 3 kinds of protein (albumin, hemoglobin and albumin-myoglobin mixture) solutions. The higher deacetylation degree and the lower molecular weight chitosan, the higher adsorption for water soluble proteins was accomplished. The optimum pHs for adsorption of albumin, hemoglobin and albumin-myoglobin mixture (4: 1, w/w) were 4.0, 7.0 and 4.0 respectively and the optimum time was $3\~4$ hrs for all proteins. Sodium chloride in the model system of protein solution was a preventing factor for protein adsorption ability of chitosan (DD=$80\%$, MW=350 kDa).

• Journal of Applied Biological Chemistry
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• v.65 no.4
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• pp.457-462
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• 2022

Manganese (Mn) exists in various oxidation states and Mn(II) is the most mobile species of Mn, which is toxic to plants and limits their growth. Therefore, the purpose of this study was to reduce Mn toxicity by immobilizing Mn using various adsorbents including iron oxides and calcium compounds. Ferrihydrite, schwertmannite, goethite were synthesized, which was confirmed by X-ray diffraction. Hematite was purchased and used as Mn adsorbent. Calcium compounds such as CaNO₃, CaSO₄, and CaCO₃ were used to increase pH and oxidize Mn. For Mn adsorption, Mn(II) solution was reacted with four iron oxides, CaNO₃, CaSO₄, and CaCO₃ for 24 hours, filtered, and the remaining Mn concentrations in the solution were analyzed by inductively coupled plasma optical emission spectroscopy. The adsorption rate and adsorption isotherm were calculated. Among iron oxides, the adsorption rate was highest for hematite followed by ferrihyrite, but goethite and schwertmannite did not adsorb Mn. In the case of calcium compounds, the adsorption rate was high in the order of CaCO₃>CaNO₃>CaSO₄. In conclusion, treatment of CaCO₃ was the most effective in reducing Mn toxicity by increasing pH.

• Journal of the Korean Wood Science and Technology
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• v.28 no.2
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• pp.49-56
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• 2000

This study was designed to investigate the adsorption of heavy metal ions by untreated bark according to the treatment conditions of aqueous solution. The effect of temperature and pH of aqueous solution, particle size of bark, addition of light metal ions on the adsorption was examined, and the competition in adsorption among heavy metal ions was also evaluated. te The adsorption ratio of $Cu^{2+}$ and $Zn^{2+}$ increased with increasing themperature of solution from $-5^{\circ}C$ to $10^{\circ}C$ however, it was relatively constant at temperatures between $10^{\circ}C$ and $55^{\circ}C$. The adsorption ratio of $Cr^{6+}$ increased continuously with increasing the temperature of solution. The maximum adsorption ratio of $Cu^{2+}$, $Zn^{2+}$, and $Pb^{2+}$ was noted at pHs ranged 6 to 7; however, the adsorption ratio declined sharply on either sides of the optimum. The adsorption ratio of $Cr^{6+}$ decreased continuously with increasing the pH of solution. The adsorption ratio increased as decreasing the particle size of bark, and there was little differences in adsorption tendency between pine and oak bark. By the addition of $Ca^{2+}$ or $Mg^{2+}$(10~25 ppm), the adsorption ratio of $Cu^{2+}$ and $Zn^{2+}$ increased. An increase of the adsorption ratio was higher in oak bark than in pine bark. However, the adsorption ratio of $Pb^{2+}$ and $Cr^{6+}$ was not affected by the addition of light metal ions. As the mixed solution of 2 or 3 kinds of heavy metal ions($Cu^{2+}$, $Zn^{2+}$, $Pb^{2+}$) was treated with the untreated bark, the adsorption of $Zn^{2+}$ decreased considerably because of the competitive adsorption among heavy metal ions. Also the adsorption of $Cu^{2+}$ was more and less reduced. However the adsorption of $Pb^{2+}$ was not affected by the presence of other heavy metal ions.

• Polymer(Korea)
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• v.30 no.4
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• pp.291-297
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• 2006

In this study, adsorption properties of oxidized NO by plasma using aminated polyolefin-g-GMA hybrid anion exchange fibers were investigated. The maximum conversion of $NO_2$ by plasma was 49% at the conditions of 200 ppm NO, 10% $O_2$ and 30 L/min of flow rate. The adsorption content for N02 of hybrid anion exchange fibers increased with increasing the swelling ratio and the highest value was 1.5 g $H_2O/g$ IEF. The adsorption of $NO_2$ by hybrid anion exchange fibers were very fast until 10 min and reached its maximum value of 80% at 120 min. Ion exchange capacity of hybrid anion exchange fibers increased with increasing the swelling ratio and it showed the highest 0.6 mmol/g IEF values at L/D=5. The adsorption isotherm model for hybrid anion exchange fibers were closer to Freundlich than Langmuir adsorption isotherm model. It was shown that adsorption of the multi-molecular layer was dominant.

• Textile Coloration and Finishing
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• v.18 no.4
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• pp.43-48
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• 2006

A phthalocyanine reactive dye was applied to nylon fibers to study the effects of the temperature and pH on % exhaustion and fixation. In addition, appropriate predictable empirical models, relatively new approaches in dyeing process, were developed incorporating interactions effects of temperature and pH for predicting the both % exhaustion and fixation. The significance of the mathematical model developed was ascertained using Excel regression (solver) analysis module. A very high correlation coefficient was obtained ($R^2=0.9895$ for % exhaustion, $R^2=0.9932$ for fixation) for the model which shows prominent prediction capacity of the model for the unknown conditions. The predictable polynomial equations developed from the Experimental results were thoroughly analyzed by ANOVA (Analysis of Variance) statistical concepts.

• KSBB Journal
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• v.16 no.2
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• pp.128-132
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• 2001

Cyclodextrin glucanotransferase (EC 2.4.1.19 : 1,4-$alpha$-glucan 4-$alpha$-D-(1,4-glucano) transferase, cyclizing; CGTase) was recovered by starch adsorption. The adsorption and desorption of CGTase to starch was studied as a function of pH, temperature, and starch type. The optimal pH, temperature, and starch for adsorption were, 8.0, $4^{circ}C$, and 1% (w/v) corn starch, respectively, per 205 U/mL enzyme activity in the presence of 25% (w/v) ammonium sulfate. The maximum adsorption ratio was 95%. On the other hand, the optimal pH, temperature, and starch type for desorption were 8.0 (tris-buffer), $50^{circ}C$, and oxidized starch, respectively. The maximum desorption ratio was 98% by tris-buffer solution at pH 8.0. The efficiency of adsorption and desorption were affected slightly by the removal of cells from the fermentation broth.