• Macromolecular Research
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• v.11 no.5
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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.

• Fashion & Textile Research Journal
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• v.8 no.4
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• pp.458-464
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• 2006

The adsorption ability of heavy metal ions from the aqueous solution by chitosan, which it is well known natural biopolymer, has been investigated. The fundamental study in this research is focusing on the physicochemical adsorption utilizing the chitosan as a organic chelating adsorbent, adsorb especially heavy metal ions from the waste liquid solution. The adsorption ability of the chitosan between metal ions, having different characteristics with Mw of 188,600, 297,200, and 504,200 g/mol and degree of deacetylation (DD) of 86.92% and 100% were investigated targeting on the $Ni^{2+}$, $Co^{2+}$, $Zn^{2+}$, and $Pb^{2+}$ ions, respectively. The uptake of heavy metal ions with chitosan was performed by atomic absorption flame emission spectrophotometer (AAS) as conducted residual metal ions. It was found that chitosan has an strong adsorption capacity for some metals under certain conditions. Chitosan, which have 100% degree of deacetylation showed high adsorption recovery ratio and have an affinity for all kinds of heavy metals. In contrast, the molecular weight of chitosan was not completely affected on metal ion adsorption.

• Nuclear Engineering and Technology
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• v.32 no.5
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• pp.504-513
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• 2000

The adsorption characteristics of methyl iodide generated from the simulated off-gas stream on various adsorbents such as silver ion-exchanged zeolite (AgX), zeocarbon and activated carbon were investigated. An extensive evaluation was made on the optimal silver ion-exchanged level for the effective removal of methyl iodide at temperature up to 38$0^{\circ}C$. The degree of adsorption efficiency of methyl iodide on silver ion-exchanged zeolite is strongly dependent of silver ion-amount and process temperature. The influence of temperature, methyl iodide concentration and silver ion-exchanged level on the adsorption efficiency is closely related to the pore characteristics of adsorbents. It would be facts that the effective silver ion-exchanged level was about 10 wt%, based on the degree of silver utilization for the removal of methyl iodide.

• Journal of Pharmaceutical Investigation
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• v.4 no.1_2
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• pp.25-30
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• 1974

The adsorption of nalidixic acid on human erythrocytes was found to expressed by Freundlich's isotherm. The amount of adsorption of nalidixic acid on erythrocytes increased with an increase of pH. The adsorption of nalidixic acid on human plasma was found to expressed at Scatchard's equation by the equilibrium dialysis method. An influence of pH on adsorption of nalidixic acid to human plasma proteins was studies at pH 4-10. It was found that the degree of adsorption increase with the increase of pH from 4-6, but descreased above pH 9.

• Polymer(Korea)
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• v.26 no.5
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• pp.551-558
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• 2002

It was observed that adsorption characteristics of sulfonated fabric ion-exchanger for separating nickel ion from electroplating rinse water. Swelling ratio was increased by increasing degree of sulfonation and polarity of solvent. Ion-exchange capacity was also increased by increasing degree of sulfonation and showed 3.38 meq/g at 16% sulfonated ion-exchanger. There was little effects of pH. Adsorption equilibrium was attained within 10 min, and adsorption rate was 7.5 mg/min. Adsorption capacity was not changed after 7 cycles of regeneration process. Regeneration adsorption capacity was slightly decreased to 2.01 meq/g. It confirmed that durability of sulfonated fabric ion-exchanger was suitable for adsorption process. Adsorption equilibrium time was linearly increased by increasing L/D and adsorption capacity showed the ion exchange capacity within the range of 2.71 ∼ 3.01 meq/g in continuous process. Design of adsorption column could be possible for L/D<2. Under constant L/D condition, there is no little pH effect when rinse water is acidic solution, and operation condition of adsorption process was optimized under pH 5.

• Analytical Science and Technology
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• v.12 no.2
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• pp.159-165
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• 1999

The adsorption and separation behaviors of transition metal ions using a merrifield resin bound 1,12-diaza-3,4:9,10-dibenzo-5,8-dioxacyclopentadecane (NTOE) and 1,12,15-triaza-3,4:9,10-dibenzo-5,8-dioxacycloheptadecane(NDOE) were investigated in aqueous solution. The orders of adsorption degree(E) and distribution ratio(D) of transition metal ions were Cu(II)$t_R$) of metal ions were affected by adsorption degree(E) and distribution ratio(D). This results showed good separation efficiency of Ag(I) from mixed metal solution.

• Analytical Science and Technology
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• v.11 no.4
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• pp.248-253
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• 1998

The adsorption and separation behaviors of alkali, alkaline earth and transition metal ions using a poly-dibenzo-18-crown-6 were investigated in aqueous solution. The adsorption degree(E) and distribution ratio(D) of alkali, alkaline earth metal ions were Li(I)$t_R$) of metal ions were affected by the adsorption degree(E) and distribution ratio(D). This results showed good separation efficiency of K(I), Sr(II), Ag(I) and Pb(II) from the mixed metal solution.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.11
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• pp.1146-1152
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• 2005

Graft copolymers were synthesized from methylcellulose(MC) and acrylic acid(AA) with active carboxyl groups in the presence of potassium persulfate($K_2S_2O_8$) initiator to enhance adsorption capacity of toxic heavy metal such as $Pb^{2+}$ and $Cu^{2+}$ from wastewater. The resulting grafted copolymers(MC-g-AA/PAA) were mixture of the graft copolymers from MC and AA(MC-g-AA) and polyacrylic acid homopolymers(PAA). The degree of palling was increased with rising concentration of monomer and initiator under the reaction conditions at $60^{\circ}C$, 3 hrs. The water insoluble property of MC-g-AA showed more than 19.7% degree of grafting. So that it could be an adsorbent of heavy metals. Adsorption characteristics of the MC-g-AA were evaluated depending on the degree of grading, pH of wastewater, adsorption time, dosage of MC-g-AA and concentration of heavy metals in the different conditions. Degree of grafting, and initial concentration of heavy metal ions increased, the adsorption amount of $Pb^{2+}$ and $Cu^{2+}$ increased, but added MC-g-AA increased, the adsorption amount per unit weight of $Pb^{2+}$ and $Cu^{2+}$ decreased. The MC-g-AA showed the high $Pb^{2+}$ and $Cu^{2+}$ adsorption amount in the range pH $4{\sim}6$. Also all of $Pb^{2+}$ and $Cu^{2+}$ ions reached in adsorption equilibrium in neighborhood 4 hours. The adsorption of heavy metals described by Freundlich isotherm, it was determined the value of l/n of $Pb^{2+}$ and $Cu^{2+}$ that 0.4294 and 0.3453, respectively.

• Polymer(Korea)
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• v.26 no.1
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• pp.121-127
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• 2002

We investigated uranium adsorption and adsorption process characteristics in brine water, changing column bed height packed with amidoximated polypropylene-g- acrylonitrile (AOPP-g-AN) fibrous ion-exchanger. Swelling ratios of AOPP-g-AN in fibrous ion-exchanger were 8.54g/g $H_2O_2$ and 8.87 g/g for $H_2O_2$ solvent respectively. Ion exchange capacity increased with degree of graft and showed the maximum, 3.99 meq/g at 100% degree of graft. In batch process, uranium adsorption had reached an initial equilibrium in 10 min with the adsorption rate of 9.5 mg/min. Finial adsorption capacity was 3.95 meq/g, and pH effect could not be observed. In continuous process, adsorption capacity depended on various packing ratios and showed the maximum, 3.92 meq/g at L/D=1. In L/D<2, breakthrough curve was shown two step by channeling flow and ununiform adsorption. Breakthrough time and adsorption capacity were 26 min and 3.63 meq/g, respectively, in brine water adsorption. When compared with actual brine water and model solution, there was no significant difference of adsorption characteristics.

• Korean Journal of Materials Research
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• v.27 no.3
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• pp.127-131
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• 2017

Isosteric heat of hydrogen adsorption is one of the most important parameters required to describe solid-state hydrogen storage systems. Typically, it is calculated from adsorption isotherms measured at 77K (liquid N2) and 87K (liquid Ar). This simple calculation, however, results in a high degree of uncertainty due to the small temperature range. Therefore, the original Sievert type setup is upgraded using a heating and cooling device to regulate the wide sample temperature. This upgraded setup allows a wide temperature range for isotherms (77K ~ 117K) providing a minimized uncertainty (error) of measurement for adsorption enthalpy calculation and yielding reliable results. To this end, we measure the isosteric heats of hydrogen adsorption of two prototypical samples: activated carbon and metal-organic frameworks (e.g. MIL-53), and compared the small temperature range (77~87K) to the wide one (77K ~ 117K).