• Proceedings of the Membrane Society of Korea Conference
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• 1994.10a
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• pp.66-67
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• 1994

Polysulfone은 물리적, 화학적 성질이 우수하고 내열성과 내유기용매성등이 우수한 열가소성 수지로서 투과성능도 좋고 배제율도 높아 한외여과막이나 역삼투막, 기체분리막 등에 널리 이용되고 있다. 그러나 소수성 물질이기 때문에 처리과정에 있어서 fouling 발생이 큰 문제점으로 대두되고 있다. 따라서 이러한 fouling 현상을 억제하기 위해 화학적인 개질을 통하여 친수성을 높히는 방법이 필요하다. 본 실험에서는 친수성 고분자를 얻기 위하여 $-R_3N^+$기를 치환을 통하여 도입하였다. quaternary polysulfone의 치환여부를 확인하기 위하여 NMR, FT-IR를 이용하였고, 투과도와 용질배제율을 측정하여 개질의 효과를 살펴 보았다. 그리고 이온반발력을 이용하여 염료용액의 배제율을 향상시킬 수 있었다.

• Membrane and Water Treatment
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• v.7 no.1
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• pp.39-53
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• 2016

In this study, polysufone (PSf) was used as a base polymer to synthesize sulfonated polysulfone (SPSf) and aminated polysulfone (APSf) as cation and anion exchange polymers, respectively. Then the ion exchange polymers were coated onto the surface of commercial carbon electrodes. To compare the capacitive deionization (CDI) and membrane capacitive deionization (MCDI) processes, the pristine carbon electrodes and ionic polymer coated electrodes were tested under various operating conditions such as feed flow rate, adsorption time at fixed desorption time, and feed concentration, etc., in terms of effluent concentration and salt removal efficiency. The MCDI was confirmed to be superior to the CDI process. The performance of MCDI was 2-3 times higher than that of CDI. In particular, the reverse desorption potential was a lot better than zero potential. Typically, the salt removal efficiency 100% for 100 mg/L NaCl was obtained for MCDI at feed flow rate of 15 ml/min and adsorption/desorption time of 3 min/1 min and applied voltages 1.0 V for adsorption and -0.3 V for desorption process, and for 500 mg/L, the salt removal efficiency 91% was observed.

• Journal of Industrial Technology
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• v.19
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• pp.343-350
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• 1999

The separation of humic acid by ultrafiltration was most influenced by pressure difference. when pressure difference increased from latm to 3atm, permeate flux increased from 40% to 60% but rejection rate reduced from 97% to 91% because of adsorption of molecules of humic acid at membrane surface. Since physical adsorption was more dominant than chemical adsorption, adsorption of membrane surface was reduced 50% when slow rate increased at same conditions.

• Proceedings of the Membrane Society of Korea Conference
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• 1998.10a
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• pp.103-105
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• 1998

Asymmetric polymeric membranes prepared by the phase transition technique usually have either a top layer consisting of closely packed nodules or pores dispersed throughout the membrane surfaces. In this study, we present AFM image of a polysulfone membrane which show a clear evidence for the nodular structure and porous structure resulted from different phase separation mechanisms; spinodal decomposition and nucleation and growth. The surface morphology obtained by SEM and AFM was also compared.

• Membrane Journal
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• v.8 no.2
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• pp.102-108
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• 1998

Permeation behavior of the semiconductor rinsing wastewater containing Si particles was examined by ultrafiltration using the polysulfone plate membrane. The permeation flux was gradually decreased with time. It was due to the growth of cake deposited on the membrane surface and the pore plugging by Si particles. Permeation flux of cross flow type was 1.4 times higher than that of the dead end flow type. Nitrogen back flushing which is the removing method of membrane fouling was superior to the water sweeping. With nitrogen back flushing, the decrease of permeation flux due to the fouling was recovered about 85 % to the initial flux in the flat plate membrane system. The rejection rate of Si particles was about 90 % and the size of Si particle in the permeate was about 70 nm.

• Membrane Journal
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• v.20 no.2
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• pp.135-141
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• 2010

Various asymmetric Polysulfone membranes were prepared for a MBR process. Ether-typed alcohols (co-solvent) were added into a dope solution in order to control the pore size of membrane, whose effect on water permeability were investigated. Pore size of the prepared membranes were more affected by molecular-structure of co-solvent than by boiling point of theirs. With the increasing order of methoxy ($CH_3$-O-) < secondary propanol ($-CH_2$-CH(OH)$-CH_3$) < ethoxy ($CH_3-CH_2$-O-), water permeability of the prepared membrane increased. The phenomenon might attribute to the difference of molecularly steric hinderance of co-solvent (eg, Methoxy propanol, Ethoxy ethanol, Methoxy ethanol) in dope solution during the phase inversion. By the addition of ether typed alcohol into a dope solution, the pore size of MF (microfiltration) could be controlled. Also, Membrane prepared was applied to a MBR process and the system was stably operated for 2 months.

• Membrane Journal
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• v.22 no.3
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• pp.224-233
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• 2012

To improve permeation performance of gas separation membrane, polysulfone hollow fiber membrane was prepared by wet-dry phase inversion method using Triton X-100 as non-ionic additive. And variation of gas permeation behavior by additive was investigated. Various spinning conditions such as air gap, concentration of polymer, dope tank temperature were controlled and these effects were studied. The morphology and gas permeation property of hollow fiber membranes were investigated using scanning electron microscope (SEM) and bubble flow meter respectively. We confirmed that the membranes added with Triton X-100 had a smooth external skin at various air gap length conditions. The macrovoids of these hollow fiber membranes were more developed with increase of air-gap from 4 to 90 cm and that induced higher permeance. The permeance of polysulfone membranes has the higher value at comparatively lower concentration polymer (30 wt% polysulfone) and lower concentration of additive (15 wt% Triton X-100). When temperature in dope tank was controlled, the membranes prepared at $100^{\circ}C$ showed low permeance because of volatilization of additive and solvent.

• Proceedings of the Membrane Society of Korea Conference
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• 2005.05a
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• pp.100-103
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• 2005

• Membrane Journal
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• v.18 no.4
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• pp.317-324
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• 2008

Polysulfone membranes were prepared via the phase inversion process. With propionic acid as a nonsolvent additive, polysulfone casting solutions were solidified in an isopropanol bath. Propionic acid (PA) worked as a thermodynamic enhancer for phase separation and as a rheological suppressor for kinetic hindrance. Morphology of the prepared membranes significantly varied with propionic acid content in the casting solution. The dense skin layer, which was identified in the membrane prepared without PA, almost disappeared in the membrane prepared trom PA 10wt%. With 30wt% PA, the membrane revealed the morphological gradient from a nodular skin structure to a sponge-like substructure, including the finger-like cavity. Water permeability increased with PA content, and polyethylene glycol rejection decreased with the nonsolvent content.

• Membrane and Water Treatment
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• v.4 no.2
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• pp.83-93
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• 2013

In the present investigation, were synthesized composite membranes prepared by simultaneous casting of two polymer solutions using the technique of phase inversion by immersion / precipitation. The support layer was prepared using polyethersulfone and polysulfone as base polymer and for the top layer was used sulfonated polysulfone (SPSU) with 50% sulfonation degree. The morphology of the resulting membranes were characterized by scanning electron microscopy (SEM). The final results showed that it is possible to prepare composite membranes by simultaneous casting of two polymer solutions with adherence between the two layers. Regarding the permeation tests, the developed membranes presented values of hydraulic permeability within the range of commercial nanofiltration (NF) membranes. Values rejection of 80% ammonium ions can be increased by using a SPSU with a greater degree of sulfonation.