• Title/Summary/Keyword: ion-exchange reaction

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Synthesis of Sulfonated PET-g-GMA Fine Ion-exchange Fibers for Water Treatment by Photopolymerization and Their Adsorption Properties for Metal Ions (광중합법을 이용한 수처리용 설폰산형 PET-g-GMA 극세 이온 교환 섬유의 합성 및 금속 이온 흡착 특성)

  • Kwak Noh-Seok;Hwang Taek-Sung;Kim Sun-Mi;Yang Yun-Kyu;Kang Kyung-Seok
    • Polymer(Korea)
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    • v.28 no.5
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    • pp.397-403
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    • 2004
  • The sulfonated PET-g-GMA ion-exchange fine fibers were synthesized by UV radiation-induced graft copolymerization using a photoinitiator, and their chemical structure and adsorption properties were investigated. The optimum values for synthetic conditions - UV intensity, reaction time, and reaction temperature were 450 W, 60 min, and $40^{\circ}C$, respectively. Maximum values of the degree of sulfonation and ion exchange capacity were 8.12 mmol/g and 3.25 meq/g, respectively. Tensile strength of sulfonated PET-g-GMA fine ion exchange fibers was lower than that of PET trunk polymer as the grafting reaction rates increased. It was shown that as for the adsorption rate of $Ca^{2+}$ and $Mg^{2+}$ by the sulfonated PET-g-GMA fine ion exchange fibers, magnesium ion is slower than calcium ion in the solution. However, in the mixture of the calcium and magnesium ions, the adsorption rate of calcium ion was much slower than that of magnesium ion.

Basic Study for Development of Denitrogenation Process by Ion Exchange(III) - A kinetic study in the batch reactor - (이온교환법에 의한 탈질소 공정개발의 기초연구(III) - 회분식 반응기에서의 반응속도론-)

  • 채용곤;이동환;김승일;윤태경;홍성수;이민규
    • Journal of Environmental Science International
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    • v.9 no.2
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    • pp.165-171
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    • 2000
  • A kinetic study for anion exchange was performed for commercially available Cl- type anion exchange resin in use to remove nitrate in water. The obtained results from the batch reactor were applied to the Langmuir and Freundlich models. The constants for Lagmuir model were qmax =29.82 and b=0.202, and for Freundlich model were K=5.509 and n=1.772. Langmuir model showed betterfit than Frendlich model for the experimental results. Ion exchange reaction rate was also calculated and the the approximate first-order reaction, rate constant k1 was 0.16 L/mg.hr. Effective diffusion coefficient was obtained in the range from $9.67$\times$10^{-8} cm^2/sec$ for initial concentration change, and from $6.09$\times$10^{-7} to 3.98$\times$10^{-6} cm^2/sec$ for reaction temperature change. Activation energy during the diffusion was calculated as 26 kcal/mol.

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On the Reaction of Montmorillonit with Cysteamin (Montmorilloint와 Cysteamin의 반응(점토의 효율적인 이용을 위한 기초연구-1))

  • 신건철
    • Journal of the Korean Ceramic Society
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    • v.20 no.4
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    • pp.361-365
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    • 1983
  • The Cation Exchange Isotherm of $Na^+$ Montmorillonit with Cysteammonium ion is determined. It is shown that Cysteammonium ion is bonded relatively good on the silicate interlayer of Montmorilloint. And it is also shown that the bonded $HSCH_2CH_2NH_3^+$ ion on the Silicate interlayer reacts with the transition metal ion $Co^+$ in is SH group.

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Sulfonation of Polyamide Containing Carboxylic Acid (Carboxylic acid를 함유한 sulfonated polynmide의 제조)

  • Jeon, Jong-Young;Lee, Gi-Jo
    • Journal of Sericultural and Entomological Science
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    • v.48 no.1
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    • pp.1-5
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    • 2006
  • Polyamide containing carboxylic acid was sulfonated with chlorosulfonic acid in dichloroethane under various conditions. The impact of the sulfonating agent concentration, the reaction temperature, and the reaction time on the ion exchange capacity was investigated. The mechanical and thermal properties, the contact angle, and the change of poly-dispersity were calculated for studying change of their properties. The reactions were effective, when the temperature was below $10^{\circ}C$ and the concentration of chlorosulfonic acid was below 0.05 mol. The value of ion exchange capacity was increased with reaction time. Thermal and mechanical properties were nearly unchanged according to the degree of sulfonation, but the contact angle was increased with increasing the value of ion exchange capacity.

The Removal of Heavy Metals in Aqueous Solution by Hydroxyapatite (Apatite를 이용한 중금속 제거)

  • 강전택;정기호
    • Journal of Environmental Science International
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    • v.9 no.4
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    • pp.325-330
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    • 2000
  • The hydroxyapatite (HAp) for the present study was prepared by precipitation method in semiconductor fabrication and the crystallized at ambient to 95$0^{\circ}C$ for 30min in electric furnace. The ion-exchange characteristics of HAp for various heavy metal ions such as $Cd^{2+}, Cu^{2+}, Mn^{2+}, Zn^{2+}, Fe^{2+}, Pb^{2+}, Al^{3+}, and Cr^{6+}$ in aqueous solution has been investigated. The removal ratio of various metal ions for HAp were investigated with regard to reaction time, concentration of standard solution, amount of HAp and pH of solution. The order of the ions exchanged amount was as follws: $Pb^{2+}, Fe^{3+}>Cu^{2+}>Zn^{2+}>Al^{3+}>Cd^{2+}>Mn^{2+}>Cr^{6+}. The Pb^{2+}$ ion was readily removed by the Hap, even in the strongly acidic region. The maximum amount of the ion-exchange equilibrium for $Pb^{2+}$ ion was about 45 mg/gram of HAp. The HAp would seem to be possible agent for the removal of heavy metal ions in waste water by recycling of waste sludge in semiconductor fabrication.

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Electrochemical Behaviors of Sparteine-Copper (II) Dihalide

  • Sung-Nak Choi;Jin-Hyo Park;Young-In Kim;Yoon-Bo Shim
    • Bulletin of the Korean Chemical Society
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    • v.12 no.3
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    • pp.276-281
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    • 1991
  • Electrochemical behaviors of optically active sparteine-Cu(II) dihalide complexes were investigated by polarography and cyclic voltammetry (CV). These Cu(II) complexes are rather easier to be reduced to Cu(I) states when comparison is made with other nonplaner copper complexes, We have assigned the CV peaks and polarographic waves related to the redox processes for these complexes. We could also observe the exchange reaction of Cu(II) ion in the complex with mercury metal in the cell having mercury pool. The redox mechanism of these complelxes is as follows; The 1st wave appeared at +0.47 V/+0.65 V corresponds to the reaction of $SpCuX_2+ e{\rightleftarrow}SpCuX_{2^-}$ and the 2nd one at +0.26 V/+0.21 V does the reaction of $SpCuX_{2 ^-} +e{\rightleftarrow}SpCuX_2^{2-}$. The 3rd one at -0.35 V/-0.27 V is dueto the reduction of mercury complex formed via exchange reaction. Where, X is chloride ion.

Synthesis of Lithium Titanate Whisker Using Ion-Exchange of Acid Treatment

  • Um Myeong-Heon;Lee Jin-Sik
    • Korean Journal of Materials Research
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    • v.14 no.9
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    • pp.627-633
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    • 2004
  • Lithium titanate whiske($Li_{x}Ti_{4}O_9$) was prepared by an ion-exchange reaction. To this end, the initial material, potassium tetratitanate ($K_{2}Ti_{4}O_9{\cdot}nH_{2}O$) was prepared by calcination of a mixture of $K_{2}CO_3\;and\;TiO_2$ with a molar ratio of 2.8 at $1050^{\circ}C$ for 3 h, followed by boiling water treatment of the calcined products for 10 h. Fibrous potassium tetratitanate could be transformed into layered hydrous titanium dioxide ($H_{2}Ti_{4}O_9{\cdot}nH_{2}O$) through an exchange of $K^{+}\;with\;H^{+}$ using 0.075 M HCl. Also, lithium titanate whisker was finally prepared as $Li^{+}\;and\;H^{+}$ ions were exchanged by adding 20 mL of a mixture solution of LiOH and $LiNO_3$ to 1g whisker and stirring for $5\~15$ days. The average length and diameter of the $Li_{x}Ti_{4}O_9$ whiskers were $10\~20{\mu}m\;and\;1\~3{\mu}m$, respectively.

The Effect of PAA on the Characterization of PVA/SSA ion Exchange Membranes (Poly(vinyl alcohol)/sulfo-succinic acid 이온교환막에 poly(acrylic acid)첨가에 따른 특성 연구)

  • 임지원;천세원;홍상혁;황호상;정성일
    • Membrane Journal
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    • v.13 no.2
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    • pp.118-124
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    • 2003
  • The ion exchange membranes prepared from the reaction between poly(vinyl alcohol) (PVA) which is known as the good methanol barrier in pervaporation membrane processes and sulfo-succinic acid (SSA) was used as the basic membranes. In order to improve the ion exchange capacity, poly(acrylic acid) (PAA) was added to this ion exchange membranes. The methanol permeabilities, ion conductivities, water contents and ion exchange capacity were measured for the resulting membranes with varying PAA contents. In general, methanol permeability and ion conductivity of PVA/SSA/PAA membranes were less than those of PVA/SSA membranes due to the reduction of free volumes resulted from crosslinking. The vehicle mechanism could be more dominant than jump mechanism for membranes in question.

A Study on the Flaking Mechanism of Glass (유리의 Flaking 생성기구에 관한 기구)

  • 김명석;심명재;김정환;이기강
    • Korean Journal of Crystallography
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    • v.11 no.4
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    • pp.224-230
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    • 2000
  • We have been investigated the flaking mechanism of the soda-line glass. The pH of aqueous solution approached to 10 and increased with reaction time by ion exchange reaction between Na/sup +/ ion of glass and H/sup +/ ion of aqueous solution under the conditions of below pH 9 of start solution. The relationship between the pH of solution and reaction time shows logarithm. Total dissolution reaction of glass components by OH/sup -/ ion in aqueous seems to be dominant after the pH solution reached to 10 and the dissolution rate linearly increased with reaction time. The above tow reactions are simultaneously occurred. The dissolved Ca/sup 2+/ ions are reprecipitated on the glass surface to Ca-compound. The flakes are formed by the separation of leached layer of glass due to the different thermal expansion coefficient.

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