• Bulletin of the Korean Chemical Society
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• v.30 no.1
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• pp.264-266
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• 2009

• Membrane Journal
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• v.22 no.2
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• pp.142-154
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• 2012

In order to remove $CO_2$ from the DME plant process, we investigated the composite membrane with rubbery polymers as the separation layer and its separation performance of $CO_2$ and $H_2$. Hollow fiber membranes for supporting layer were prepared by solution spinning method. In case of using PDMS as a separation layer, the composite membranes showed the permeation rates of $CO_2$ were over 300 GPU and minimum $CO_2/H_2$ selectivitties were 4.3 and in case of using PEBAX as a separation layer, the composite membranes showed the permeation rates of $CO_2$ were over 120 GPU and minimum $CO_2/H_2$ selectivities were 5.

• Membrane Journal
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• v.9 no.3
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• pp.185-192
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• 1999

The ultrafiltration characteristics of wafer processing wastewater produced from semicon¬ductor industry was investigated for wastewater reuse. Using the pilot-scale ultrafiltration system con¬taining poly sulfone hollow fiber membranes (MWCO : 10,000, 20,000, 30,(00), the membrane performance, such as flux, rejection rate and concentration factor for flux was examined. The SDhs, turbidity, electrical conductivity and concentration of Si particles were measured, and the possibility of permeate reuse was validated from the experimental results. It was shown that the flux was recovered by the sweeping with air and water effectively. The permeate flux of 30,000 MWCO membrane was about 5 times higher than that of 10,000 and 20,000 MWCO membranes. The concentration of Si particle in the saw wastewater was analyzed 3.8-5.6 mg/$\ell$ and that of Si particle in the permeate was analyzed less than 0.2${\mu}g$/$\ell$. This means the rejection of silicon particle was over 96%.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1332-1335
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• 2003

This paper presents the enhancement of oxygen transfer efficiency using the vibrating intravascular lung assist device (VIVLAD) in in-vitro experiments for patients having chronic respiratory problems. The test section was a cylinder duct with the inner diameter of 30 mm. The flow rate was controlled by the pump and monitored by a built-in flow meter. The vibration apparatus was composed of a piezo-vibrator, a function generator. and a power amplifier. The direction of vibration was radial to the fluid flow. Gas flow rates of up to 6 l/min through the 120-cm-Jong hollow fibers have been achieved by exciting a piezo-vibrator. The output of PVDF sensor were investigated by various frequencies in VIVLAD. The experimental results showed that VIVLAD would be enhance oxygen transfer efficiency.

• 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.

• Proceedings of the Membrane Society of Korea Conference
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• 1999.07a
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• pp.95-96
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• 1999

The ultrafiltration behavior of dilute colloidal solution containing Si particles has been investigated. The experiments in cross flow mode have been performed at different operating condition by using the membrane with 20 kDa cut-off. The flux decline was due to the development of membrane fouling which was a dynamic process of two distinctive stages. For the high trans-membrane pressure, the pore blocking resistance was dominant at the initial period of filtraion and was followed by the cake resistance. And for the low cross flow velocity, the membrane fouling was governed by the cake filtration model at the initial stage of filtration process. Flux jump was observed temporally during the membrane filtration of mixed feed solution.

• Korean Chemical Engineering Research
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• v.57 no.3
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• pp.313-320
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• 2019

Extraction/separation of cobalt by supported liquid membrane has been reviewed. The review discusses various directions associated with the supported liquid membrane process, such as the kind of supported liquid membrane, the principle of supported liquid membrane, transport mechanism involved, and the advantages and disadvantages of the supported liquid. Finally, extraction and separation of cobalt from other metals using extractant through supported liquid membrane have been reviewed. Separation of cobalt using various reagents and cobalt recovery from scrap using commercial extractant can be a potential perspective from the application of supported liquid membrane application.

• Membrane Journal
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• v.11 no.2
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• pp.66-73
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• 2001

Ivlain objectives of this work arc to investigate basic fouling characteristics and emxts of backpulsing on the fouJing control in the free-end membrane module uo

• Polymer(Korea)
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• v.37 no.3
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• pp.288-293
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• 2013

A group of molecularly imprinted polymers (MIPs) with specific recognition for chiral (S)-ibuprofen were successfully prepared based on hydrogen bonds, utilizing ${\alpha}$-methacrylic acid as a functional monomer. The IR analysis of MIPs showed that the blue- and red-shifted hydrogen bonds were formed between templates and functional monomers in the process of self-assembly imprinting and re-recognition, respectively. According to UV-Vis analysis, we found that the ratio of host-guest complexes between template molecule and functional monomer was 1:1. The effect of cross-linker's quantity on the polymerization was studied by transmission electron microscope (TEM). The adsorption selectivity experiments indicated that MIPs exhibited higher selectivity to (S)-ibuprofen than those to ketoprofen and (R)-ibuprofen, (S)-ibuprofen's structural analogs.

• Membrane Journal
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• v.2 no.2
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• pp.122-128
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• 1992

A study on the citric acid production was performed in various size dual hollow fiber bioreactors with immobilized Aspergillus niger (KCTC 1232). The final dry cell mass density reached 300g/l based on the space volume available for cell growth. Under air and oxygen aeration the volumethe productivity reached 0.63 and 1.02g/l.h, which cormsponded to 10 and 16 fold over those of batch fermentation, respectively. The initial pH of the medium was a critical factor and the lower value resulted in higher citric acid yield. The increase in the feeding rate of medium or the number of reactor unit resulted in the improvement of the productivity due to higher consumption rate of substrate.