• Membrane and Water Treatment
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• v.3 no.4
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• pp.243-252
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• 2012

Tri-n-butyl phosphate (TBP) was used as carrier for the transport of Golden yellow and Cibacron LSG dyes through a hexane bulk liquid membrane. The transport efficiency of dyes by TBP was investigated under various experimental conditions such as pH of the feed phase (dyes solution), concentration of the receiving phase (NaOH solution), concentration of TBP in membrane, rate of stirring, effect of transport time, type of solvent, dye concentration in feed phase, effect of temperature.. The maximum transport dyes occurs at ratio of 1:1 TBP-hexane At pH 3.0 0.1 (feed phase) the transport dyes decreased. At high stirring speed (300 rpm) the dyes transport from the feed phase to the strip phase was completed within 60 minutes at $27^{\circ}C$. Under optimum conditions: Feed phase 100 mg/L dyes solution at pH 1.0 0.1, receiving phase 0.1 mol/L NaOH solution, membrane phase 1:1 TBP-hexane , Stirring speed 300 rpm and temperature $27^{\circ}C$, the proposed liquid membrane was applied to recover the textile effluent.

• Korean Journal of Microbiology
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• v.29 no.5
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• pp.267-269
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• 1991

The hyphal tip laccase of Coprinus congregatus which is a membrane-associated enzyme and shows diffdrdnt banding patterns of PAGE analysis when compared with the enzyme of liquid culture (Choi et al. 1987) has been successfully secreted to culture medium in liquid shake culture by lowering the pH of medium to 4.0. When the fungus is cultivated in YpSs(pH 4.0) liquid, only the hyphal tip laccase is found in the medium after 6 hr incubation and there is no liquid-type enzyme when examined by PAGE analysis.

• Membrane and Water Treatment
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• v.3 no.4
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• pp.231-242
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• 2012

The performance of a nanofiltration membrane for treatment of a low-level radioactive liquid waste was investigated through static and dynamic tests. The liquid waste ("carbonated water") was obtained during conversion of $UF_6$ to $UO_2$. In the static tests membrane samples were immersed in the waste for 24, 48 or 72 h. The transport properties of the samples (hydraulic permeability, permeate flow, selectivity) were evaluated before and after immersion in the waste. In the dynamic tests the waste was permeated in a permeation flow front system under 0.5 MPa, to determine the selectivity of NF membranes to uranium. The surface layer of the membrane was characterized by zeta potential, field emission microscopy, atomic force spectroscopy and infrared spectroscopy. The static test showed that the pore size distribution of the selective layer was altered, but the membrane surface charge was not significantly changed. 99% of uranium was rejected after the dynamic tests.

• Membrane Journal
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• v.25 no.3
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• pp.216-222
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• 2015

The method measuring LEP (liquid entry pressure) was optimized to evaluate the wettabilities of hydrophobic membranes which might affect long-term durability of membrane in MD (membrane distillation) process. Conductivity of the permeate was monitored to measure the LEPs of PE (polyethylene) and PVDF (polyvinylidene di-fluoride) hollow fiber membranes from highly concentrated synthetic feed water of 20 wt% NaCl. Holding time over 5 min and the ratio of membrane area to the tank volume more than $10m^2/m^3$ were required to ensure LEP value.

• Proceedings of the Membrane Society of Korea Conference
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• 1998.04a
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• pp.62-64
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• 1998

1. 서론 및 이론적 배경 : 분리막 기술은 다양한 산업분야에서 광범위하게 사용되어지고 있는데 대부분 비대칭형 구조를 지닌 다공막이다. 이 경우 막의 표면에 존재하는 기공의 크기 및 크기 분포가 분리막의 성능을 결정하게 된다. 분리막 표면의 active pore 크기 및 크기 분포를 측정하기 위하여 liquid displacement방법이 많이 사용되고 있다. (생략)

• Bulletin of the Korean Chemical Society
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• v.17 no.12
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• pp.1109-1111
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• 1996

The Podand Ⅰ (Figure 1) has been studied as cation carrier in a bulk liquid membrane system. Ag+ and some other transition metal ions (M2+=Cu, Ni, Co, Zn, and Cd) have been transported using the podand as carrier in a bulk liquid membrane system. Studies on the transport of equimolar mixtures of two or three competing components have also been carried out with the same system. Ag+ exhibited a higher transport rate than the other M2+ in the competitive experiments. Ligand structure and the equilibrium constant for complex formation are important parameters in the transport of the metal ions.

• Membrane Journal
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• v.30 no.3
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• pp.149-157
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• 2020

Ionic Liquid (IL) in the category of low-temperature molten salts with organic cation and organic/inorganic anion has shown great potentiality in CO₂ gas separation. CO₂ gas separation from flue gas by IL based membrane has been widely researched in recent years to overcome climate change and global warming. Membranes based on free standing polyionic liquid (PIL), blend of ionic liquid and composite ionic liquid membranes are discussed in this review. Introducing different IL monomers and tuning microstructure of PIL membrane and composite of PIL-IL to enhance mechanical properties of membranes with good CO₂ gas permeability and selectivity. Variations in cation and anions of monomer has great impact on the membrane gas separation performance.

• Bulletin of the Korean Chemical Society
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• v.24 no.4
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• pp.489-493
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• 2003

2-Mercaptobenzothiazole was used as a highly selective and efficient carrier for the uphill transport of silver ion through a chloroform bulk liquid membrane. In the presence of thiosulfate ion as a suitable metal ion acceptor in the receiving phase, the amount of silver transported across the liquid membrane after 180 min was 90 ± 3.0%. The selectivity and efficiency of silver ion transported from aqueous solutions containing equimolar mixtures of $Zn^{2+}, Cu^{2+}, Co^{2+}, Ni^{2+}, Cd^{2+}, Pb^{2+}, Bi^{3+}, Fe^{2+}, Fe^{3+}, Pd^{2+}, Mn^{2+}, Hg^{2+}, Sn^{2+}, Ca^{2+}, Mg^{2+}, K^+, Na^+ and Li^+$ were investigated.

• Bulletin of the Korean Chemical Society
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• v.33 no.10
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• pp.3387-3390
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• 2012

In this research work the potentialities of microemulsion bulk liquid membrane for the selective transport of L-tryptophan (L-Trp) and L-tyrosine (L-Tyr) are investigated at 298.15 K. Reversed micelle formed by sodium bis(2-ethylhexyl)sulfosuccinate (AOT) in dichloroethane, was used as mobile carrier to transport amino acids between a source and a receiving aqueous phase. The effects of pH, surfactant concentration and initial amino acid concentration on the extraction efficiency and transfer rate of the amino acids were studied. It is verified that for a mixture of two amino acids, L-Trp can be extracted selectively by using this type of the bulk liquid membrane with optimized condition.

• Proceedings of the Membrane Society of Korea Conference
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• 2004.05a
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• pp.74-77
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• 2004

Porous membranes were prepared via thermally induced phase separation (TIPS) of (ethylene-co-vinyl alcohol) (EVOH)/glycerol mixtures. The liquid-liquid (L-L) phase boundaries are shifted to higher temperature when the ethylene contents in EVOH increase. Moreover, the kinetic study proved that the growth of droplets formed by the general liquid-liquid (L-L) phase separation obeyed a power-law scaling relationship in the later stage of spinodal decomposition (SD). A new phase separation mechanism was presented, in which the L-L phase separation could be resulted from the crystallization. The hollow fiber membranes were prepared. The membranes showed asymmetric structures with skin layer near the outer surface, the larger pores just below the skin layer and the smaller pores near the inner surface. The effect of ethylene content (EC) in EVOH, cooling water bath temperature and take-up speed on membrane performance was investigated.