• Membrane Journal
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• v.22 no.6
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• pp.435-440
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• 2012

In this study, nanoporous HKUST-1 membranes were synthesized by solvothermal method. It is very difficult to prepare uniform and crack-free HKUST-1 layer on macroporous alumina support by in-situ solvothermal method. In this study, continuous and crack-free HKUST-1 membranes could be obtained by spraying solvothermal precursor solution on the heated alumina support, followed by solvothermal synthesis. HKUST-1 membranes were characterized by XRD, FE-SEM and single gas permeation experiments.

• Applied Chemistry for Engineering
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• v.28 no.4
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• pp.420-426
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• 2017

Recently, solvent-resistant nanofiltration membranes have been studied for the separation of solvents or solutes using a molecular weight cut-off system of the polymer which is resistant to a specific solvent. Required conditions for these membranes must have are excellent physical properties and solvent resistance. Polybenzimidazole, which is known to be one of the most heat-resistant commercially available polymers, has an excellent inherent solvent resistance and it is even insoluble in stronger organic solvents when cross-linked. Therefore, in this study, the applicability of polybenzimidazole as a solvent resistant nanofiltration membrane was discussed. The membrane was fabricated using the non-solvent induced phase separation method and showed a suitable morphology as a nanofiltration membrane confirmed by field emission scanning electron microscopy. In addition, the permeance of the solvent in the presence or absence of cross-linking was investigated and the stability was also confirmed through long operation. The permeance test was carried out with five different solvents: water, ethanol, benzene, N, N-dimethylacetamide (DMAc) and n-methyl-2-pyrrolidone (NMP); each of the initial flux was $6500L/m^2h$ (water, 2 bar), $720L/m^2h$ (DMAc, 5 bar), $185L/m^2h$ (benzene, 5 bar), $132L/m^2h$ (NMP, 5 bar), $65L/m^2h$ (ethanol, 5 bar) and the pressure between 2 and 5 bar was applied depending on the type of membrane.

• Resources Recycling
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• v.12 no.1
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• pp.25-32
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• 2003

A study on the separation of heavy metals such as iron, copper, zinc and nickel from electroplating waste water has been investigated. The results showed that the PC-88A was more effective extractant for the extraction of zinc and the efficiency of zinc was to be about 100% at pH 2.5. And copper and nickel were extracted about 100% at pH 2 and more than 90% at pH 4～5 with LIX 84, respectively. On the other hand, in the case of solvent extraction of electroplating waste water(Acid-Alkali type) containing heavy metals, the ferric ion was first extracted at pH 2∼2.5 with 20% Naphthenic acid or 10% Versatic acid-10. And then, copper and zinc were extracted at pH 2 with 3% LIX 84 and at pH 2.5∼3 with 20% PC-88A respectively, remaining nickel in the raffinate. In this manner, the heavy metals in electroplating waste water could be effectively separated with solvent extraction method.

• Applied Chemistry for Engineering
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• v.8 no.4
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• pp.694-699
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• 1997

Normal-phase HPLC was used to separate the useful phospholipids, PE, PI and PC in soybean lecithin. The mobile phase used in this experiments were haxane, isopropanol and methanol, the gradient mode was applied as the three components could not be separated by the isocratic mode. To find the optimum separation condition, the concentration profiles of effluents were calculated from the plate theory and the capacity factor in step-gradient mode. From the calculated results, PE was separated with hexane/isopropanol/methanol = 90/5/5vol.% in isocratic mode and PI and PC were resolved in the conditions of 10min gradient time and the second mobile phase of hexane/isopropanol/methanol=50/20/30vol.% in step-gradient mode. The agreement between the calculated concentration profile and experimental data was good, so the methodology developed in this work can be used to obtain the optimum separation condition in gradient mode.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.165-168
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• 2002

TLC(Thin Layer Chromatography) 는 제약산업이나 생화학 연구 그리고 여러 산업 현장에서 널리 이용되는 화학 분석 방법이다 . 본 연구에서는 적은 비용으로도 많은 양의 시료를 신속하게 분리할 수 있는 TLC를 이용하여 유기산인 젖산 (Lactic acid) 을 분리는 전개방법을 개발하였다 . 전개용매는 2 가지 용매 (1) nitroethane nitromethane : ethanol: water: I-propanol = 1 : 2 : 3 : 4 : 5 (v/v/v/v/v), (2) diisopropyl ether. formic acid. water = 90 : 7 : 3 (v/v/v) 를 사용하였다 . 발색시약은 A : bromocresol purple reagent I, B . bromocresol purple reagent II, C : bromocresol green-bromophenol blue-potassium permanganate reagent 를 사용하여 분석하는 방법을 개발하였다 $^6)$. 젖산의 분리는 silica gel TLC plate를 이용하는 경우 , 용매 (1) 에 발색시약 B를 사용했을 때 , 분리 확인이 가장 좋았다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.797-799
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• 2010

In preparation of NBD dimer, one of the industrially useful multicyclic hydrocarbon compound, various catalyst, solvent and byproducts were included in reaction product at the end of dimerization reaction. In order to increase the yield of NBD dimer mixture, first of all, effective separation process development was required. The research for improvement of NBD dimer yield were performed by use of eco-friendly and recyclable separation solvent.

• Proceedings of the Membrane Society of Korea Conference
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• 1998.04a
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• pp.70-71
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• 1998

1. 서론 : 상업적으로 널리 사용되고 있는 cellulose acetate, polysulfone 등과 같은 막 소재는 유기용매에 대한 화학적 안정성이 떨어지므로 새로운 막분리 소재가 필요로 되고 있다. 기계적 강도, 열적 안정성이 뛰어난 Polyimide 는 거의 모든 종류의 유기용매에 대한 안정성이 우수하여 비수계용 한외여과의 분야에서 높은 잠재력을 지니고 있다. 그러나 Polyimide 는 대부분의 유기용매에 녹지 않으므로 상전환방법에 의한 비대칭막을 제조하기가 어려웠다. (생략)

• Proceedings of the Membrane Society of Korea Conference
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• 1996.04a
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• pp.42-43
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• 1996

고분자 분미막을 이용한 분리기술은 기존의 분리기술에 비하여 에너지의 절약과 높은 분리효율 등의 장점이 있어 거의 모든 산업에 이용되고 있다. 분리막의 용도가 다양화됨에 따라서 내열성, 내약품성, 내유기용매성을 갖는 막소재의 개발이 필요하게 되었다. polyimide(PI)게의 고분자는 물리, 화학적 성능이 우수하고 내열성과 내유기용매성 등이 우수한 열가소성수지로서 film, sheet, tubular형으로 만들 수 있어 한외여과막이나 역삼투막, 기체분리막 등에 이용되고 있다. 그러나 투과속도를 높디고, fouling을 줄이기 위해서는 화학적 개질을 통해 친수성을 높이는 방법이 필요하다. 본 실험에서는 내열성과 내유기용매성이 우수한 polyetherimide계 고분자를 chlorosulfonic acid(CSA)를 이용하여 술폰화시킴으로써, 극성기의 도입에 의해 친수성이 향상된 sulfonated polyetherimide(SPEI)를 합성하였다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.5 no.2
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• pp.174-185
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• 2004

Organic pollutants (Phenol, 2-Chlorophenol, Nitrobenzene) were separated from wastewater by nondispersive membrane solvent extraction, using a microporous hydrophobic hollow fiber module. The system was operated countercurrently and cocurrently with the aqueous phase flowing through the fiber lumens and the solvent flowing through the shell side. The distribution coefficients of several solvents (MIBK, IPAc, Hexane) were examined and MIBK was selected as an extracting solvent. Separation efficiency of countercurrent flow method was better than that of cocurrent flow method. Also, the overall mass transfer coefficients were determined.

• Clean Technology
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• v.14 no.4
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• pp.275-280
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• 2008

In this study, we carry out economic and technical feasibility study for treatment process of waste solvent such as SD waste solution and stripper solution from LCD manufacturing process. Extensive screening work has been done for selecting the best extraction solvent. As a result, it is shown that $CHCl_3$ is the most adequate extraction solvent for separation and recovery of both SD waste solvent and stripper waste. Rigorous simulation study has been carried out for extraction process and distillation process as a candidate of waste solvent treatment. The result shows that the solvent extraction process is more beneficial than the simple distillation process.