• Title/Summary/Keyword: silica gel, zeolite

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Growth of Zeolite-X Crystals on Metal Sieves Surface by Continuous Crystallization Method (연속적인 결정화 방법에 의한 금속 지지체상에서 Zeolite-X의 결정성장)

  • Park, Jeong-Hwan;Suh, Jeong-Kwon;Jeong, Soon-Yong;Lee, Jung-Min;Doh, Myung-Ki
    • Applied Chemistry for Engineering
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    • v.8 no.6
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    • pp.939-944
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    • 1997
  • The films of zeolite X on the surface of metal sieve were prepared by continuous crystallization method. It is known that the growth of zeolite crystal on the surface of metal is mainly dependent on the surface composition of metal sieve. In the present work, the zeolite nuclei could be easily formed as Cr content on the metal surface was removed by acid treatment. In order to investigate the proedure growing of zeolite crystal by the continuous crystallization method, the composition of zeolite X($6.36Na_2O-Al_2O_3-5.3SiO_2-190.8H_2O$)was supplied every 12hour. Then the mechanism and inter-relationship between the metal surface and nucleation are investigated. The results show that as the content of silica increases in the gel mixture, the nuclei of zeoilite are easily formed on the metal surface. Also, it was confirmed that the particle of zeolite stuck on the metal surface continues the linear growth. The particles are combined by the reaction of polycondensation, and finally become the shape of crystal. The sample synthesized by the film type was confirmed as zeolite X by the analyses of SEM and XRD.

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Sorption of Radioactive Cobalt and Ruthenium on Soil Minerals (방사성 코발트 및 루테늄의 토양 흡착)

  • Lee, Byung-Hun;Hands, J.D.
    • Journal of Radiation Protection and Research
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    • v.15 no.2
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    • pp.7-16
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    • 1990
  • The sorption of radioactive cobalt and ruthenium on alumina, silica gel, zeolite 3A, kaolin and Na-bentonite has been studied as a function of pH. nuclide concentration and ionic strength. Retardation factor for cobalt and ruthenium on soil minerals was determined through porosity measurement. Hydrolysed species, cobalt and ruthenium interact with solid surfaces by physical adsorption processes. Freundlich sorption isotherms for cobalt and ruthenium are effectively linear. The sorption decreases with increasing ionic strength for cobalt and ruthenium. The effect of increasing porosity on the retardation factor countered the effect of a significant increase in the distribution coefficient.

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A Study on the Characterizations of Silica-Ceramic Paper Dehumidifiers Impregnated with Zeolites (제올라이트가 도포된 실리카-세라믹 제습제의 특성)

  • Jung, Suk-Yong;Lee, Soo-Chool;Chae, Ho-Jin;Lee, Soo-Jae;Park, Jung-Je;Ahn, Young-Soo;Kim, Hong-Su;Kim, Jae-Chang
    • Clean Technology
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    • v.14 no.1
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    • pp.40-46
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    • 2008
  • The dehumidifiers were prepared by the impregnation of the zeolites such as MCM 48, USY, beta on the silica ceramic paper. Their capacities for $H_2O$ absorption and regeneration of the bed were tested in a fixed bed reactor system. The $H_2O$ absorption capacities of the dehumidifiers impregnated with the zeolites were $1.5{\sim}2$ times higher than those without the zeolites. Especially, the humidifier using MCM 48 and colloidal silica showed an excellent capacity (42.1g $H_2O/g$ absorbent). It was found that the $H_2O$ absorption capacities of the dehumidifiers were improved because the amount of silica gel, the main component in absorbing $H_2O$, increased due to the large surface area and pore volume of the zeolites. In addition, $H_2O$ was easily desorbed from the dehumidifiers with zeolites at $80^{\circ}C$ of regeneration temperature and the desorption amount of $H_2O$ was the same as that absorbed. It was confirmed that the $H_2O$ absorption capacities of the dehumidifiers impregnated with zeolite were maintained without deactivation through the repeated cyclic experiments.

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The Stability of Aging and Synthetic Development of Paper Mending Tape for Conservation of Archive Document (종이 기록물 보수용 테이프 점착제 합성 및 열화 안전성 연구)

  • Shin, Joung-Soon;Lee, Kwi-Bok
    • Journal of the Korean Graphic Arts Communication Society
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    • v.30 no.1
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    • pp.35-45
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    • 2012
  • Polyacrylate dispersion(emulsion) as adhesive material was superior in quality such as preservation characteristics and reversibility. The tapes for repairing archival documents manufactured with four different types of formulation resulted in pH 7~8.8, soluble solid 50~52%, and viscosity 1,300~2,500 cps. Sample 4 of those was most excellent. Probably, sample 4 included inorganic materials such as MgO, silica gel, and zeolite. For selecting carrier of tape, tracing papers, were applied for manufacturing tapes and tested for adhesive strength and peel strength. Adhesive strength of tracing papers, was 3.1~3.8(N/10mm), 2.2~2.8(N/10mm), and 1.7-2.3(N/10mm), respectively. Peel strength was similar in all samples. To determine characteristic of conservation to the selected carriers, stability of deterioration was examined at conditions of $105^{\circ}C$ and $80^{\circ}C$ 65% for 7 days.

Performance Test of Low Temperature Regeneration Polymeric Desiccant Rotor (고분자 제습로터의 저온재생 성능시험)

  • Lee, Jin-Kyo;Lee, Dae-Young;Oh, Myung-Do
    • Proceedings of the SAREK Conference
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    • 2009.06a
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    • pp.629-632
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    • 2009
  • The polymeric desiccant rotor is made from the super absorbent polymer by ion modification. The moisture sorption capacity of the super desiccant polymer(SDP) is 4 to 5 times larger than those of common desiccant meterials such as silica gel or zeolite. It is also known that SDP can be regenerated even at the relatively low temperature. To fabricate the desiccant rotor, firstly the SDP was laminated by coating the SDP on polyethylene sheet. Then corrugated and rolled up into a rotor. The diameter, the depth, the dimensions of the corrugated channel, etc. were pre-determined from numerical simulation on the heat and mass transfer in the desiccant rotor. The dehumidification performance was tested in a climate chamber. The relevant tests were carried out at the process air inlet temperature of $32^{\circ}C$, the regeneration air inlet temperature of $60^{\circ}C$ and the inlet dew-point temperature of both the process air and the regeneration air of $18.5^{\circ}C$, when the rotation period is long, the moisture sorption is not effective. In the desiccant rotor developed in this study, the optimum rotation period is found about 350s at the regeneration temperature of $60^{\circ}C$. It was found from further experiments that the optimum rotation tends to decreases as the regeneration temperature increases. Meanwhile, the outlet temperature of the process air deceases monotonically as the rotation period increases.

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