• Membrane Journal
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• v.29 no.2
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• pp.105-110
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• 2019

Porous membranes are widely used in industry for removing particulate matter. Unlike conventional porous membrane fabrication methods, the solution spreading phase separation method can form pores very simply. The first step is to wet the mesh with the support layer, then to let the polysulfone solution flow into a solvent without water. The solvent is readily vaporized and the polysulfone is made into a thin film. When the polysulfone solution is mixed with water to form pores, the pore size can be adjusted according to the concentration ratio of the polysulfone solution. The thickness of the membrane is easily controlled by the concentration of the solution. The porous separator has the formation of meshes intact and is very useful for forming a three-dimensional structure. The solution spreading phase separation method proposed in this study is characterized by its high cost competitiveness compared with conventional membranes due to its low production cost and easy process control.

• Economic and Environmental Geology
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• v.43 no.6
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• pp.555-564
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• 2010

Remediation process by using the bio-carrier (beads) with dead Bacillus sp. B1 and polysulfone was investigated for heavy metal contaminated groundwater. Sorption batch experiments using the bio-carrier were performed to quantify the heavy metal removal efficiencies from the contaminated solution. The analyses using SEM/EDS and TEM for the structure and the characteristic of precipitates on/inside the beads were also conducted to understand the sorption mechanism by the bio-carrier. Various amounts of freeze-dried dead Bacillus sp. B1 were mixed with polysulfone + DMF(N,N-dimethylformamide) solution to produce the bio-carrier (beads; less than 2mm in diameter) and 5% of Bacillus sp. B1 in the bio-carrier was optimal for Pb removal in the solution. The removal efficiency ratings of the bio-carrier for Pb, Cu and Cd were greater than 80% after adding 2g of bio-carrier in 50ml of aqueous solution (<10mg/L of each heavy metal concentration). Reaction time of the bio-carrier was very fast and most of the sorption reaction for heavy metals were completed within few hours. Batch experiments were duplicated at various pH conditions of aqueous solutions and Cu and Pb removal efficiencies highly maintained at wide pH ranges (pH 2-12), suggesting that the bio-carrier can be useful to clean up the acidic waste water such as AMD. From SEM/EDS and TEM analyses, it was observed that the bio-carrier was spherical shape and was overlapped by many porous layers. During the sorption experiment, Pb was crystallized on the surface of porous layers and also was mainly concentrated at the boundary of Bacillus sp. B1 stroma and polysulfone substrate, showing that the main mechanism of the bio-carrier to remove heavy metals is the sorption on/inside of the bio-carriers and the bio-carriers are excellent biosorbents for the removal of heavy metal ions from groundwater.

• Journal of the Korean Society of Industry Convergence
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• v.4 no.1
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• pp.77-85
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• 2001

This paper was to investigate the preparation of polysulfone(PS), polyethersulfone(PES) and polyphenylsulfone(PPS) membrane. The thermal property of PPS was higher than that of others. From the result of SEM, the concentration of polymer was found to have a significant effect on the structure of membrane, and the structure of membrane made of PES is found to have regular micell form of asymmetry. Permeability and selectivity for oxygen and nitrogen gas in the air were analyzed by GC. Permeabilities of the membrane made of PES for oxygen and nitrogen in air, 1.5 and $0.7(x10^9[cm^3(STP)cm/cm^2seccmHg]) $, respectively was higher than that of others. and Selectivity of the membrane made of PPS for oxygen to nitrogen gas in air was 2.9.

• Membrane and Water Treatment
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• v.9 no.5
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• pp.353-361
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• 2018

Fouling characteristics of humic substances on tight ultrafiltration (UF) membrane have been investigated. The tight UF membrane was prepared by blending polysulfone (PSf) in N.N-dimethylacetamide (DMAc) with 25%wt of Polyethylene glycol (PEG400) and 4%wt of acetone. Fouling characteristic of the modified PSf membrane was observed during peat water filtration in different trans-membrane pressure (TMP). It was found that the acetone modified membrane provided 13% increase in TMP during five hours of peat water filtration, where a stable flux was reached within 150 minutes. Meanwhile, the increase of TMP from 10 psig to 30 psig resulted in a fouling resistance enhancement of 60%. Furthermore, based on the fouling analysis, fouling mechanism at the first phase of filtration was attributed to intermediate blocking while the second phase was cake formation.

• Proceedings of the Membrane Society of Korea Conference
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• 1993.10a
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• pp.34-35
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• 1993

The study was undertaken to investigate the effects of ZnCl$_2$ in polysulfone(PSf)/N-methylpyrrolidone(NMP) on the structure and performance of its membrane. The effects of additives on the performances of membranes have been studied. It has been shown that some low molecular weight additives in polysulfone(PSf) casting solutions have effects on the performances of membranes cast from these solutions. It had been reported that ZnCl$_2$, as the additives-in PSf casting solution, decreases water permeability and increases the rejection rate of its membrane.

• Journal of Environmental Science International
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• v.20 no.10
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• pp.1233-1241
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• 2011

The main objective of this experimental investigation was $CH_4$ recovery from biogas generated in municipal and wastewater treatment plant. The polysulfone hollow fiber membrane was prepared in order to investigate the permeation properties of $CH_4$ and $CO_2$. Permeability of $CO_2$ in Polysulfone membrane was 11-fold higher than of $CH_4$ gas. A membrane pilot plant for upgrading biogas was constructed and operated at a municipal wastewater treatment plant. The raw biogas contained 66 ~ 68 Vol % $CH_4$, the balance being mainly $CO_2$. The effect of the operating pressure of feed and permeate side and feed flowrate on $CH_4$ recovery concentration and efficiency were investigated with double stage membrane pilot plant. The $CH_4$ concentration in the retentate stream was raised in these tests to 93 Vol % $CH_4$.

• Membrane and Water Treatment
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• v.8 no.6
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• pp.591-612
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• 2017

Increase in the hydrophilicity (HPCT) of polysulfone (PS) membrane and subsequently decrease in fouling can be achieved by surface modification of PS based membranes. Therefore, in this work, ultrafiltration membranes with increased HPCT were prepared using the enantiomeric tartaric acid (D-TA) and racemic tartaric acid (DL-TA). Phase inversion technique was used for the preparation of polyethylene glycol and TA blended PS membrane. Morphological analysis of the fabricated membranes was done by scanning electron microscope and atomic force microscopy. Bovine serum albumin (BSA) solution was taken for finding the permeation and rejection behavior of prepared membranes. Maximum BSA rejection was increased by 70.5% for the modified membrane.

• Macromolecular Research
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• v.10 no.4
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• pp.209-214
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• 2002

Miscibility of polysulfone (PSf) with various hydrophilic copolymers was explored. Among these blends, PSf gives homogeneous mixtures with poly(1-vinylpyrrolidone-co-styrene) copolymers [P(VP-S)] when these copolymers contained VP from 68 to 88 wt%. Microporous membranes for the ultrafiltration process were prepared from PSf blends with P(VP-S) copolymers. The membranes prepared from the PSf/(VP-S) blends exhibited higher water flux than the membranes prepared from PSf irrespective of the VP content. The solute rejection examined with the membranes fabricated from the miscible blends was similar to that of PSf membrane. However, the solute rejection examined with the membranes fabricated from the immiscible blends was lower than that of PSf membranes.

• Korean Membrane Journal
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• v.4 no.1
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• pp.20-24
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• 2002

The surface of polysulfone membranes has been modified using the fluorine chemicals, ITFE (2-iodo-1,1,1-trifluoro-ethane F.W.=209.94) and PFPI (1H,1H-pentafluoro-n-propyl iodide F.W.=259.95), and PFI (1H,1H,2H,2H-perfluorohexyl iodide, F.W.=373.99) based on Friedel-Crafts reaction mechanism with varying reaction temperatures, reaction time, and catalysis types. The resulting membranes were characterized through mainly the contact angle measurement and pure water permeability. The smaller reactant shows the larger contact angles. FeBr$_3$ catalyst is more effective than AlCl$_3$. Typically, the PS film treated with ITFE at $25^{\circ}C$ under FeBr$_3$ catalyst showed the contact angle 78.5$^{\circ}C$ which indicated 10% over the value of unreacted PS films. More than 50% of pure water flux 8.0 g/$m^2$hr, reduced at reaction time 10 min relative to the original flux, 3.49 g/$m^2$hr.

• Journal of Industrial Technology
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• v.23 no.A
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• pp.187-191
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• 2003

A hollow-fiber type polysulfone UF membrane was surface-coated with hydroxyethylmethacrylate (HEMA). The effect of various coating parameters on permeation flux, such as concentration ratio of AIBN/HEMA, solvent(water or methanol), and UV irradiation time, was investigated. The water permeation flux of oil-emulsion increased with concentration ratio of AIBN/HEMA, and increased with UV irradiation time. The flux of the membrane coated in solution using methanol as a solvent was greater than that of the membrane coated in solution using water as a solvent. The flux of both the coated and the uncoated membrane declined with the operation. The flux decline means that the membrane fouling by oil-emulsion occurs. However, the fouling of the coated membrane was much less than that of the uncoated membrane.