• Journal of Korean Association for Spatial Structures
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• v.16 no.2
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• pp.55-60
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• 2016

The Membrane structure has a number of problems in the application of a fireproof code based on general buildings codes. Thus, the fireproof code of membrane structure is necessary to activate the construction of the membrane structure. Because it requires a systematic classification of fire retardant and flame proof performance of membrane material. Fire retardant and flame proof tests are conducted on membrane materials mostly used in current construction to propose the fire and flame retardant performance criteria of membrane materials. Fire and flame retardant tests results, PTFE membrane material with the glass fiber fabric have a limit-combustible performance. PVDF membrane material with the polyester fabric does not ensure the fire retardant performance, but this membrane material has the flame retardant performance of a thick fabric. Also, ETFE does not ensure the fire retardant performance, but this membrane material has the flame retardant of a thin fabric.

• Membrane and Water Treatment
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• v.9 no.6
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• pp.481-487
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• 2018

Membrane clogging or fouling of the membrane caused by organic, inorganic, and biological on the surface is one of the main obstacles to achieve high flux over a long period of the membrane filtration process. So researchers have been many attempts to reduce membrane fouling and found that there is a close relationship between membrane surface hydrophilicity and membrane fouling, such that the same conditions, a greater hydrophilicity were less prone to fouling. Nanotechnology in the past decade is provided numerous opportunities to examine the effects of metal nanoparticles on the both hydrophilic and antibacterial properties of the membrane. In the present study the improvement of hydrophilic and antimicrobial properties of the membrane was evaluated by adding nanoparticles of titanium dioxide and copper oxide. For this purpose, 4% copper oxide and titanium dioxide nanoparticles with a ratio of 0, 30, 50, and 70% of copper oxide added to the polymeric membrane and compare to the pure polymeric membrane. Comparison experiments were performed on E. coli PTCC1998 in two ways disc and tube and also to evaluate membrane hydrophilic by measuring the contact angle and diameter of pores and analysis point SEM has been made. The results show that the membrane-containing nanoparticle has antibacterial properties and its impact by increasing the percentage of copper oxide nanoparticles increases.

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.2
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• pp.184-190
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• 2011

The membrane properties (membrane resistance and ion exchange capacity) of the five types of commercial anion exchange membrane, i.e. IOMAC, AHT, APS, AHA, AFN, were evaluated for the application in the alkaline electrolysis. The membrane resistance decreased in the order; in 1M KOH: AHT>IOMAC>AHA>AFN>APS; in 1M NaOH: AHT>IOMAC>AHA>APS>AFN. The ion exchange capacity decreased in the order: AFN>APS>AHT>AHA>IOMAC. The membrane life was determined from the change of membrane resistance in 1M KOH and NaOH with an increase of soaking time in 20 wt% KOH and 30 wt% NaOH solution. AHA membrane had a good membrane life in 20 wt% NaOH with its unchanged membrane resistance. And, AFN and AHA membrane had a good membrane life in 30 wt% NaOH with its unchanged membrane resistance.

• Membrane and Water Treatment
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• v.13 no.4
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• pp.191-199
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• 2022

In industrial production, the development of traditional polyamide nanofiltration (NF) membrane was limited due to its poor oxidation resistance, complex preparation process and high cost. In this study, a composite NF membrane with high flux, high separation performance, high oxidation resistance and simple process preparation was prepared by the method of dilute solution dip coating. And the sulfonated polysulfone was used for dip coating. The results indicated that the concentration of glycerin, the pore size of the based membrane, the composition of the coating solution, and the post-treatment process had important effects on the structure and performance of the composite NF membrane. The composite NF membrane prepared without glycerol protecting based membrane had a low flux, when the concentration of glycerin increased from 5% to 15%, the pure water flux of the composite NF membrane increased from 46.4 LMH to 108.2 LMH, and the salt rejection rate did not change much. By optimizing the coating system, the rejection rate of Na₂SO₄ and PEG1000 was higher than 90%, the pure water flux was higher than 40 LMH (60psi), and it can withstand 20,000 ppm.h NaClO solution cleaning. When the post treatment processes was adjusted, the salt rejection rate of NaCl solution (250 ppm) reached 45.5%, and the flux reached 62.2 LMH.

• Korean Membrane Journal
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• v.7 no.1
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• pp.67-70
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• 2005

It is well known as the role of ion exchange membrane with functional group in membrane matrix. Recently, we were reported that the charged mosaic membrane within parallel array of negative and positive charge groups. In this study we are reported the properties for the various transport coefficients of metal and heavy metal ions across charged mosaic membrane based on non-equilibrium thermodynamics is not based on equilibrium state.

• Membrane and Water Treatment
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• v.11 no.5
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• pp.323-331
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• 2020

With the increasing demand on reverse osmosis (RO) membranes for water purification worldwide, the number of disposed membrane elements is expected to increase accordingly. Thus, recycling and reuse of end-of-life RO membranes should be a global environmental action. In this work, we aim to reuse the spent RO membrane for nanofiltration (NF) and ultrafiltration (UF) process by subjecting the spent membrane to solvent and oxidizing solution treatment, respectively. Our results showed that solvent-treated RO membrane could perform as good as commercial NF membrane by achieving similar separation efficiencies, but with reduced water permeability due to membrane surface fouling. By degrading the polyamide layer of RO membrane, the transformed membrane could achieve high water permeability (85.6 L/㎡.h.bar) and excellent rejection against macromolecules (at least 87.4%), suggesting its reuse potential as UF membrane. More importantly, our findings showed that in-situ transformation on the spent RO membrane using solvent and oxidizing solution could be safely conducted as the properties of the entire spiral wound element did not show significant changes upon prolonged exposure of these two solutions. Our findings are important to open up new possibilities for the discarded RO membranes for reuse in NF and UF process, prolonging the lifespan of spent membranes and promoting the sustainability of the membrane process.

• Proceedings of the Membrane Society of Korea Conference
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• 1998.09a
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• pp.1-30
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• 1998

1. RO History 2. Asymmetric Membranes by Phase Inversion 3. Thin Film Composite (TFC) Membrane 4. Structure and Property Relationship of TFC Membrane 5. Membrane Materials 6. Tranport Mechanism(Model) 7. Membrane Characters in Separation Process 8. Concentration Polarization and Fouling Phenomenon 9. RO Membrane Module Configuration and System Design 10. Futrue Trend in RO Industry

• Membrane Journal
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• v.13 no.1
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• pp.1-8
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• 2003

Membrane filtration systems have been focusing and increasing rapidly in the filed of drinking water treatment because of several reasons. We describe briefly the present state of membrane filtration processes for drinking water treatment in Japan: including background, objectives, membrane suppliers, and some cases of actual plants.

• Journal of the Korean Applied Science and Technology
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• v.35 no.2
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• pp.472-477
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• 2018

The excess molar volumes of a general anesthetics on Purple membrane and Red membrane separated by extraction in Halobacteriun Halobium and in suspensions of vesicle have been determined at $25^{\circ}C$, it was used a excess volume dilatometer. The anesthesia characteristics of general anesthetics, Propofol was fined by our study to correlate with excess molar volume. Excess volume changes of the vesicle measured by excess volume dilatometer, which is an important amino acid and lipid in the purple membrane and red membrane by means of specific weight in Halobacteriun Halobium, were studied by absorption intensity at 280 nm and 330 nm. The particle size analysis and relative turbidity of Purple membrane and Red membrane by means of Propofol were measured for mechanical properties. In the samples where Propofol is incoporated in vesicle, especially, the excess molar volume of PM + RM + Propofol is the greatest than the excess molar volumes of PM, and RM.

• Membrane Journal
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• v.28 no.3
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• pp.143-156
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• 2018

In this review article, hybrid water/wastewater treatment processes of membrane and photocatalyst were summarized from papers published in various journals. It included (1) membrane photoreactor (MPR), (2) fouling control of a membrane coupled photocatalytic process, (3) photocatalytic membrane reactors for degradation of organic pollutants, (4) integration of photocatalysis with membrane processes for purification of water, (5) hybrid photocatalysis and ceramic membrane filtration process for humic acid degradation, (6) effect of $TiO_2$ nanoparticles on fouling mitigation of ultrafiltration membranes for activated sludge filtration, (7) hybrid photocatalysis/submerged microfiltration membrane system for drinking water treatment, (8) purification of bilge water by hybrid ultrafiltration and photocatalytic processes, and (9) Hybrid water treatment process of membrane and photocatalyst-coated polypropylene bead.