• 제목/요약/키워드: separation of mixtures

검색결과 310건 처리시간 0.03초

개질 비대칭 폴리에테르이미드막을 통한 물-이소프로판올 혼합물의 투과증발 분리: 투과증발 특성에 미치는 표면층 개질에 사용된 NaOH 농도의 영향 (Pervaporation Separation of Water-isopropanol Mixtures Through Modified Asymmetric Polyetherimide membranes: the Effect of NaOH Concentration for the Modification of Skin Layers on the Pervaporation Characteristics)

  • 김상균;제갈종건;이규호
    • 공업화학
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    • 제10권2호
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    • pp.319-323
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    • 1999
  • 비대칭 폴리에테르이미드막을 상전이 방법으로 제조하였고, 표면층 개질에서 NaOH 농도의 영향과 그에 따른 물/이소프로판올 혼합물 투과증발 분리에 대하여 연구하였다. 실험결과, 개질 용액의 농도가 증가할수록 폴리에테르이미드의 이미드 그룹이 가수분해에 의해서 쉽게 폴리아믹산 구조로 변하여 치밀층의 두께가 증가하였다. 따라서 사용된 NaOH 농도가 증가할수록 전반적인 투과도는 감소하였고, 선택도는 증가하였다. 그러나 NaOH 용액의 농도가 너무 높은 경우, 선택도가 오히려 감소하고 투과도는 증가되었다. 이러한 결과로부터, 비대칭 폴리에테르이미드막의 투과거동이 NaOH 농도에 크게 의존한다는 것을 알 수 있었다. 또한, NaOH로부터 개질된 막들의 투과증발 운전온도가 증가할수록 투과도와 선택도가 모두 증가되었다.

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Application of Membranes for Organic Liquid or Vapor Separation and Design of Plasma-Graft Filling-Polymerized Membranes

  • Yamaguchi, Takeo;Nakao, Shin-ichi
    • 한국막학회:학술대회논문집
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    • 한국막학회 1996년도 추계 총회 및 학술발표회
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    • pp.34-39
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    • 1996
  • There is much recent interests in applying membrane separation technologies, especially for organic liquid and vapor separation or removing dissolved organics from water. Pervaporation separation can separate azeotropic mixtures and mixtures close to boiling point, and it has a potential for energy saving process instead of distillation. Removal of chlorinated oraganics from water is other measure application for pervaporation separation. Contaminated pollutant must be removed from water, and a pervaporation can effectively remove the pollutant. Air pollution by organic vapor recently became serious enviromncntal problem, and removing organic vapor from air is important application of the membrane technology.

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Flexible Nonlinear Learning for Source Separation

  • Park, Seung-Jin
    • Journal of KIEE
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    • 제10권1호
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    • pp.7-15
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    • 2000
  • Source separation is a statistical method, the goal of which is to separate the linear instantaneous mixtures of statistically independent sources without resorting to any prior knowledge. This paper addresses a source separation algorithm which is able to separate the mixtures of sub- and super-Gaussian sources. The nonlinear function in the proposed algorithm is derived from the generalized Gaussian distribution that is a set of distributions parameterized by a real positive number (Gaussian exponent). Based on the relationship between the kurtosis and the Gaussian exponent, we present a simple and efficient way of selecting proper nonlinear functions for source separation. Useful behavior of the proposed method is demonstrated by computer simulations.

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Silver Polymer Electrolyte Membranes for Facilitated Olefin Transport: Carrier Properties, Transport Mechanism and Separation Performance

  • Kim, Jong-Hak;Kang, Yong-Soo
    • Macromolecular Research
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    • 제12권2호
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    • pp.145-155
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    • 2004
  • Facilitated transport membranes for the separation of olefin/paraffin mixtures have long been of interest in separation membrane science because olefins, such as propylene and ethylene, which are important chemicals in petrochemical industries, are currently separated by energy-intensive cryogenic distillation processes. Recently, solid polymer electrolyte membranes containing silver ions have demonstrated remarkable performance in the separation of olefin/paraffin mixtures in the solid state and, thus, they can be considered as alternatives to cryogenic distillation. Here, we review recent progress, and critical issues affecting in the use of facilitated olefin transport membranes; in particular, we provide a general overview with reference to carrier properties, transport mechanisms, and separation performance.

NaA 제올라이트 분리막의 물/에탄올 투과증발 특성 (Pervaporation Characteristics of NaA Zeolite Membrane for Water/Ethanol Mixture)

  • 안효성;이혜련;이용택
    • Korean Chemical Engineering Research
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    • 제43권2호
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    • pp.243-248
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    • 2005
  • 분리막 투과증발은 증류에 비하여 낮은 에너지를 요구하기 때문에 물/유기물 혼합물의 분리에 이용될 수 있으며 공비 혼합물이나 이성질체의 분리에 선호되는 방법이다. 제올라이트 분리막은 고분자 분리막에 비하여 열적, 기계적, 화학적 안정성이 우수하며 NaA 제올라이트 분리막은 큰 친수성을 나타내므로 물/유기물 혼합물로부터 효율적인 물 분리에 적합하다. 본 연구에서는 NaA 제올라이트 분리막을 이용한 투과증발 막분리 공정을 이용하여 물/에탄올 혼합물에서 선택적으로 물을 분리하고자 하였다. 에탄올의 공급 농도가 증가함에 따라 총투과플럭스는 감소하였으며 선택도는 증가한 후 높은 에탄올 농도에서 감소하는 것을 관찰할 수 있었다. 실험 온도의 증가에 따라 총투과플럭스는 증가하였으며 선택도 또한 증가하였지만 높은 에탄올 농도에서는 감소하였다. 160시간 이상의 장기간 실험을 통하여 총투과플럭스와 선택도가 안정적으로 일정함을 확인할 수 있었다. 또한, 본 연구를 통하여 얻어진 NaA 제올라이트 분리막은 증류 및 PVA 계열 고분자 분리막보다 우수한 성능을 나타냄을 알 수 있었다.

Separation of Dichlorinated Bydrocarbons by Pervaporntion Using ZSM-5 Zeolite Membrane

  • Lee, Young-Jin;Lee, Hye-Ryeon;Shim, Eun-Young;Ahn, Hyo-Sung;Lee, Yong-Taek
    • Korean Membrane Journal
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    • 제7권1호
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    • pp.51-57
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    • 2005
  • Pervaporation with a membrane is one of the economic technologies for separation of liquid mixtures including organic/water mixtures. The ZSM-5 membrane was used fur pervaporation of dichloromethane, 1,2-dichloroethane and trans-1,2-dichloroethylene from their aqueous solutions since its physical property shows very hydrophobic. ZSM-5 crystals were hydrothermally grown and deposited on the inside of a porous sintered stainless steel tube by the secondary growth method. Fluxes of dichlorinated organic compounds were observed to be $50{\~}429\;g/m^2/h$ while separation factors were $15{\~}320$ depending on a mole fraction of a dichlorinated organic compound in a feed solution ranged from 0.0001 to 0.001 mole fraction and the operation temperature between $25^{\circ}C\;and\;35^{\circ}C$.

Pervaporation Separation of Water-Acetic Acid Mixtures Through Poly(vinyl alcohol) Membranes Crosslinked with Glutaraldehyde

  • Yeom, Choong-Kyun;Lee, Kew-Ho
    • 한국막학회:학술대회논문집
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    • 한국막학회 1994년도 추계 총회 및 학술발표회
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    • pp.32-33
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    • 1994
  • Poly(vinyl alcohol)(PVA) membranes crosslinked with Glutaraldehyde (GA) were prepared for the separation of acetic acid-water mixtures. For the preparation of the crosslinked membranes, dry PVA films were immersed for 2 days at 40$\circ$C in reaction solutions which contain different content of GA solution(25% GA in water), aceton and a catalyst, HCl. IR spectroscopy was employed to characterize the crosslinking reaction between hydroxyl groups in PVA and aldehyde groups in GA. Swelling measurements of the crosslinked membranes were carried out in both water and acetic acid to investigate the crosslinking density and swelling behaviour of the membranes.

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