• 멤브레인
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• 제2권1호
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• pp.36-36
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• 1992

This paper deals with the separation of MTBE-methanol mixtures using crosslinked Poly(vinyl alcohol)(PVA) membranes with sulfur-succinic acid(SSA) as a crosslinking agent by pervaporation and vapor permeation technique. The operating temperatures, methanol concentration in feed mixtures, and SSA concentrations in PVA membranes were varied to investigate the separation performance of PVA/SSA membranes and the optimum separation characteristics by pervaporation and vapor permeation. And also, for PVA/SSA membranes, the swelling measurements were carried out to study the transport phenomena. The swelling measurements were carried out for pure MTBE and methanol, and MTBE/methanol=90/10, 80/20 mixtures using PVA/SSA membranes with varying SSA compositions. There are two factors of the membrane network and the hydrogen bonding. In pervaporation separation was also carried out for MTBE/methanol=90/10, 80/20 mixtures at various temperatures. The sulfuric acid group in SSA took an important role in the membrane performance. The crosslinking effect might be over the hydrogen bonding effect due to the sulfuric acid group at 3 and 5% SSA membranes, and this two factors act vice versa on 7% SSA membrane. In this case, the 5% SSA membrane shows the highest separation factor of 2,095 with the flux of 12.79g/㎡·hr for MTBE/methanol=80/20 mixtures at 30℃ which this mixtures show near the azeotopic composition. Compared to pervaporation, vapor permeation showed less flux and similar separation factor. In this case, the flux decreased significantly because of compact structure and the effect of hydrogen bonding. In vapor permeation, density or concentration of methanol in vaporous feed is lower than that of methanol in liquid feed, as a result, the hydrogen bonding portion between the solvent and the hydroxyl group in PVA is reduced in vapor permeation. In this case, the 7% SSA membranes shows the highest separation factor of 2,187 with the flux of 4.84g/㎡·hr for MTBE/methanol=80/20 mixtures at 30℃.

• Membrane and Water Treatment
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• 제10권2호
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• pp.165-178
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• 2019

Mixed matrix membranes (MMMs) of poly (vinyl alcohol) (PVA) containing certain amounts of H-${\beta}$ zeolite for pervaporation were manufactured by using a solution casting protocol. These zeolite-embedded membranes were then characterized with scanning electron microscope (SEM), X-ray diffraction (XRD) and swelling tests. The membrane separation performance has been examined by means of isopropanol (IPA) dewatering from its highly concentrated aqueous solutions via response surface methodology (RSM). The results have demonstrated that the influences of feed IPA composition (85-95 wt.%), feed temperature ($50-70^{\circ}C$), zeolite loading (15-25 wt.%) and their interactive influences are all statistically significant on both pervaporation flux ($398-1228g/m^2{\cdot}h$) and water/isopropanol separation factor (617-2001). The quadratic models based on the RSM analysis have performed excellently to correlate experimental data with very high determination coefficients and very low relative standard deviations. The optimal pervaporation predictions given by using the RSM models demonstrate a total flux of $953g/m^2{\cdot}h$ and separation factor of 1458, and are excellently verified by experimental results. As reflected by these results, PVA MMMs embedded with hydrophilic $H-{\beta}$ zeolite entities have performed considerably better than its pure counterpart and indicated great potential for isopropanol dehydration applications.

• 멤브레인
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• 제33권4호
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• pp.158-167
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• 2023

환경 오염과 천연 자원의 고갈에 대한 증가하는 우려는 환경적으로 지속 가능한 기술의 개발을 촉진했습니다. 퍼바포레이션은 낮은 에너지 소비, 환경 영향 및 성능 효율로 인해 최근 수십 년 동안 주목을 받아 왔습니다. 이 방법은 막이 원하는 선택도를 충족하도록 미세 조정될 수 있기 때문에 화학 종을 분리하고 유기 용매를 탈수하는 데 사용되었습니다. 역삼투 및 증류와 같은 여러 분리 공정은 실험 환경 및 산업 응용 분야에서 모두 활용되고 있습니다. 그러나 퍼바포레이션은 작동 압력 및 온도가 낮고 거부율이 높은 등 여러 이점이 있습니다. 그럼에도 불구하고, 현재 막 기술의 상태만으로는 실용적인 응용에 대한 요구를 충분하게 할 수 없습니다. 반면, 복합막은 유기 물질과 무기 물질의 장점을 모두 활용할 수 있습니다. 많은 연구들이 현재 한계를 해결하기 위해 그래핀 산화물(GO) 및 MXene (MX)과 같은 무기 나노 물질을 고분자 막에 효과적으로 통합했습니다. 이 검토는 투과증발에서의 2D 복합막의 최근 발전을 조사하고 성능 향상을 평가합니다.

• 멤브레인
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• 제7권1호
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• pp.31-38
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• 1997

유기물 탈수 공정에 적용되는 투과증발 시스템을 설계하기 위한 투과증발 시스템 모사기가 개발되었다. 모사기는 시스템 모델링 및 수치 해석 알고리즘과 관련된 simulation engine과 모사기를 Windows 환경에서 쉽게 사용할 수 있도록 한 Graphical User Interface(GUI)로 구성되었다. 모사기 구조 및 사용 방법 등을 실규모 에탄올 탈수 공정 모사를 통하여 구체적으로 설명하였으며, 모사 결과를 실제 에탄올 탈수 Pilot test에 의한 실험 결과와 비교함으로써 모사기 성능이 우수함을 입증하였다.

• Journal of Microbiology and Biotechnology
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• 제8권2호
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• pp.165-170
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• 1998

Lipase-catalyzed esterification of n-butyl oleate was carried out in n-hexane as a model reaction. The optimal activity of Candida rugosa lipase was shown in a water activity ($a_w$) range of 0.52 to 0.65 at $30^{\circ}C$. The water produced from the esterification was removed by a tubular type pervaporation system. The rate of ester formed from the enzymatic esterification was allowed to be the same as the rate of water removal by maintaining an optimal $a_w$ of the reaction system using an on-off dewatering control device. The reaction rate and yield with a$a_w$ control were increased two folds higher than the respective values for the uncontrolled reaction.

• 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.

• Membrane and Water Treatment
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• 제5권4호
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• pp.265-279
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• 2014

Pervaporation is the most promising technique for the recovery of ethanol from the fermentation system. To date, extensive research has been conducted on the exploration of membrane materials with favorable properties. In this paper, we primarily review the performance of adsorbent-filled rubbery membranes. In addition, the fundamental mechanisms of ethanol and water molecules transportation through composite membranes are demonstrated, particularly from the perspective of cluster formation. Finally, future prospects are also analyzed to develop the guidelines for the future development of excellent membrane materials for ethanol concentration. This paper is not meant to be an exhaustive overview, rather a specialized summary that allows readers to select the information appropriated to their topics.

• 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 $25^{\circ}C\;and\;35^{\circ}C$.

• 한국막학회:학술대회논문집
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• 한국막학회 1995년도 추계 총회 및 학술발표회
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• pp.33-35
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• 1995

현재 국내에서 생산되는 에탄올은 원료나 연료용으로 사용되는 합성알콜과 주류의 원료로 사용되는 발효알콜이 대부분을 차지하고 있다. 그러나 휘발유 첨가제, 연료용 알콜의 수요가 늘어날 경우 발효공정을 이용한 에탄올 연료의 사용이 늘어날 전망이며 특히 기존의 휘발유 첨가제 중 옥탄가 향상을 위한 MTBE 대신 에탄올, ETBE의 사용이 환경적인 측면이나 경제적으로 유리하다. 연로나 첨가제로서 에탄올을 사용하기 위해서는 기존의 95%의 순도를 갖는 일반에탄ㅇ올 대신에 99.5wt%이상의 고순도 에탄올을 생산하여야 하며 에탄올 농축공정 중의 하나인 Pervaporation은 국내에서 1-2년 전부터 연구가 활발히 진행되고 있으나 현재 국내에서 진행되고 있는 Pervaporation Test는 대부분 합성알콜을 이용하여 수행되었다. 이 실험에서는 주정공장에서 제조한 주정과 조주정을 이용, 현장 Pilot Test를 통해 PV System의 성능 검증, 에탄올 내 Trace 물질파악 및 필요 막면적을 이용하여 합성알콜과의 Performance비교를 수행하였다.

• Korean Membrane Journal
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• 제5권1호
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• pp.36-42
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• 2003

A Prediction of pervaporation performance was studied by solubility parameter calculation approach for the benzene/cyclohexane mixture system using rubbery blend membrane with various solubility parameters. The solubility parameter of the rubbery blend membranes were controlled with different blend ratio of the poly(acrylonitrile-co-butadiene), poly(styrene-co-butadiene) and poly(vinyl chloride). Screening of blend formulations was accomplished by simple swelling tests. When the content of NBR is increased, the swelling of both benzene and cyclohexane are decreased. However, the ratio of benzene swelling to swelling by cyclohexane (the swelling selectivity) increases. The same is true for blends in which the PVC content is increased. Adoption of a solubility parameter calculation provides an a priori methodology for seeking the best blend formulation.