• 한국수소및신에너지학회논문집
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• 제25권1호
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• pp.28-38
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• 2014

The organic-inorganic composite membrane in polymer exchange membrane fuel cells (PEMFCs) have several fascinating technological advantages such as a proton conductivity, thermal stability and mechanical properties. As the inorganic filler, silicon carbide (SiC) fiber have been used in various fields due to its unique properties such as thermal stability, conductivity, and tensile strength. In this study, composite membrane was successfully fabricated by modified-silicon carbide fiber. Modified process, as a novel process in SiC, takes reaction by phosphoric acid after oxidation process (generated homogeniusly $SiO_2$ layer on SiC fiber). The mechanical property which was conducted by tensile test of the 5wt% modified-$SiO_2@SiCf$ composite membrane was better than that of Aquivion casting membrane as well as ion cxchange capacity(IEC) and proton conductivity. In addition, the single cell performance was observed that the 5wt% modified-$SiO_2@SiCf$ composite membrane was approximately $0.2A/cm^2$ higher than that of a Aquivion casting electrolyte membrane and electrochemical impedance was improved with the charge transfer resistance and membrane resistance.

• 멤브레인
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• 제23권1호
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• pp.80-91
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• 2013

$Fe(SO_4)_2$, cyclohexanedione dioxime, phenylboronic acid을 이용하여 금속 템플레이트 중합을 실시한 후 메탄올로 세척하여 Fe(II) clathrochelate 화합물을 합성하였다. Fe(II) clathrochelate와 polyethersulfone을 이용한 유무기 복합 멤브레인을 제조하였다. 멤브레인 제조를 위하여 Fe(II) clathrochelate는 DMF, NMP, DMAC와 같은 멤브레인 제조에 이용되는 극성 아프로틱 용매에 잘 녹는 물질로 고안되었다. Fe(II) clathrochelate는 trifluorosactic acid와 같은 강산 존재하에서도 금속이 분리되지 않고 안정성이 유지되었다. UV-vis 분광법으로 용액 가용성을 확인하였으며 (i) 강산 및 (ii) 경쟁 킬레이트제를 이용하여 용액상의 안정성을 확인하였다. 유무기 복합막은 PES, PVP, TSA, Fe(II) clathrochelate를 DMF에 녹여 NIPS (비용매 유도 상전이) 방법으로 제조하였다. Fe(II) clathrochelate의 첨가는 표면의 기공 밀도의 향상, 평균기공 크기의 증가 및 유량 증가에 영향을 주었으며 상대적으로 비대칭 구조를 가지는 성능이 향상된 멤브레인을 얻을 수 있었다.

• 상하수도학회지
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• 제25권4호
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• pp.479-488
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• 2011

Nanofiltration was performed with polyaluminium chloride solutions at different pH conditions to understand effects of inorganic compounds on aluminum hydrolysis products, i.e., three distinctive groups of aluminum species: polymeric Al at low pH; $Al(OH)_3$ at neutral pH; and ${Al(OH)_4}^-$ at high pH. The PACl solution was prepared to be approximately 4.0mM and adjusted to the designated pH. The influence of inorganic compounds on Al species fouling was investigated with 4.9mM $CaCl_2$ and 3.5mM $MgSO_4$ because $Ca^{2+}$, $Mg^{2+}$, $Cl^-$, ${SO_4}^{2-}$ are the most common inorganics in the drinking water. NF membrane fouling was measured by flux decline rate. The impact of $CaCl_2$ was not significant on the individual Al hydrolysis products fouling. However, the flux decline rate was drastically changed in the presence of $MgSO_4$. The concentration of particulate matters was considerably increased possibly due to interaction between Al species and ${SO_4}^{2-}$ where $MgSO_4$ was introduced. The particulates were accumulated on the membrane and enhanced the hydraulic resistance of the cake layer. In addition, conductivity removal of the membrane was decreased when Al-hydroxide was dominant due to reduction of membrane surface charge. The rejection of $Ca^{2+}$and $Mg^{2+}$ were considerably different, which implys that composition of inorganics paly a role on conductivity removal.

• 멤브레인
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• 제11권2호
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• pp.89-95
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• 2001

상전환 공정을 이용하여 무기 fluor인 cerium activated yttrium silicate (CAYS)가 함침재로 존재하는 폴리설폰 고분자막을 제조하였다. CAYS가 포함된 제막용액을 물 또는 이소프로파놀의 비용매 욕조에 침지시켜 고형화시켰을 때, 막에 함침되는 CAYS는 침지용 비용매에 따라 뚜렷하게 다른 함침 특성을 나타냄으로써, 제막용액의 고형화 경로를 추적할 수 있는 역할을 하였다. 물욕조에 침지되어 고형화된 막에서 무기물인 CAYS가 고분자 구조에 달라붙은 형상을 보여준 반면, 이소프로파놀에 침지되어 형성된 막에서는 셀 같은 기공 부분에 모여있는 것이 확인되었다. 이러한 현상은 제막용액의 침지 과정에서 무기함침재들이 액체-액체 상분리에 형성된 고분자 희박지역으로 집중되었음을 확인시켜 주었다.

• 상하수도학회지
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• 제31권6호
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• pp.539-549
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• 2017

In water treatment process using microfiltration membranes, manganese is a substance that causes inorganic membrane fouling. As a result of analysis on the operation data taken from I WTP(Water Treatment Plant), it was confirmed that the increase of TMP was very severe during the period of manganese inflow. The membrane fouling fastened the increase of TMP and shortened the service time of filtration or the cleaning cycle. The TMP of the membrane increased to the maximum of $2.13kgf/cm^2$, but it was recovered to the initial level ($0.17kgf/cm^2$) by the 1st acid cleaning step. It was obvious that the main membrane fouling contaminants are due to inorganic substances. As a result of the analysis on the chemical waste, the concentrations of aluminum(146-164 mg/L) and manganese(110-126 mg/L) were very high. It is considered that aluminum was due to the residual unreacted during coagulation step as a pretreatment process. And manganese is thought to be due to the adsorption on the membrane surface as an adsorbate in feed water component during filtration step. For the efficient maintenance of the membrane filtration facilities, optimization of chemical concentration and CIP conditions is very important when finding the abnormal level of influent including foulants such as manganese.

• 한국막학회:학술대회논문집
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• 한국막학회 2004년도 Proceedings of the second conference of aseanian membrane society
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• pp.94-97
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• 2004

Micro/nano-sized L $a_{0.6}$S $r_{0.4}$Co $O_{3-}$$\delta$/ particles are considered to improve oxygen permeability in highly selective inorganic oxygen separation membrane. A L $a_{0.7}$S $r_{0.3}$G $a_{0.6}$F $e_{0.4}$ $O_{3-}$$\delta$/ membrane with perovskite structure is fabricated by a conventional solid-state reaction. As the oxygen permeation flux of the L $a_{0.7}$S $r_{0.3}$G $a_{0.6}$F $e_{0.4}$ $O_{3-}$$\delta$/ membrane was lower than commercial gas separation membranes, we coated the L $a_{0.6}$S $r_{0.4}$Co $O_{3-}$$\delta$/ particles to enhance the oxygen permeation flux. It has been demonstrated that the effective area of reactive free surface is an important factor in determining the effectiveness of the introduction of coating layer for oxygen permeation. The introduction of micro/nano L $a_{0.6}$S $r_{0.4}$Co $O_{3-}$$\delta$/ particles was very effective for increasing oxygen flux, as the flux was as much as 2 to 6 times higher than that of an uncoated L $a_{0.7}$S $r_{0.3}$G $a_{0.6}$F $e_{0.4}$ $O_{3-}$$\delta$/ membrane.\delta$/ membrane.>/ membrane.brane.

• 멤브레인
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• 제29권1호
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• pp.1-10
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• 2019

Poly(ether block amide) (PEBA)는 이산화탄소 분리에 매우 적합한 상용 블록 공중합체 중 하나이다. 기체분리막의 경우 높은 투과도 뿐 아니라 강한 기계적 강도 또한 필요로 한다. PEBA공중합체의 결정성 폴리아마이드(polyamide) 블록은 기계적 강도를 제공하며 동시에 rubbery한 폴리에테르(polyether) 부분은 이산화탄소와의 친화도를 부여하여 이산화탄소 촉진 수송에 기여한다. PEBA공중합체에서 결정성 상과 rubber한 상의 조성은 기체분리막에 적합하게 조절될 수 있다. PEBA 공중합체를 기반으로 한 분리막은 좋은 투과도를 갖지만 추가적으로 분자체 효과를 이용하여 큰 기체 투과도 손실 없이 분리막의 선택도를 향상시킬 수 있다. 혼합 매질 분리막은 혼합막의 한 종류로서 고분자 매트릭스와 유기 첨가제로 이루어져 있다. 하지만 고분자 매트릭스와 유기 첨가제간의 양립성(compatibility)에 따른 문제점 또한 존재한다. 따라서 본 총설에서는 PEBA 공중합체를 기반으로 한 혼합막의 장점과 한계에 대해 다루고자 한다.

• KIEE International Transactions on Electrophysics and Applications
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• 제5C권4호
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• pp.165-170
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• 2005

A series of inorganic-organic hybrid membranes were prepared with a systematic variation of titanium dioxide nanoparticle content. Their water uptake, methanol permeability and proton conductivity as a function of temperature were investigated. The results obtained show that the inorganic oxide network decreases the proton conductivity and water swelling. It is also found that increase in inorganic oxide content leads to decrease of methanol permeability. In terms of the morphology, membranes are homogeneous and exhibit good adhesion between inorganic domains and the polymer matrix. The properties of the composite membranes are compared with the standard nafion membrane.

• 한국막학회:학술대회논문집
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• 한국막학회 2008년도 춘계 총회 및 학술발표회
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• pp.134-137
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• 2008

• 한국막학회:학술대회논문집
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• 한국막학회 2000년도 추계 총회 및 국제학술발표회
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• pp.134-135
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• 2000

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