• Korean Chemical Engineering Research
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• v.57 no.5
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• pp.596-605
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• 2019

Proton-conducting perovskite ceramic materials are highly promising for solid electrolytes as well as catalysts at high temperatures. Therefore, they possess an outstanding potential for the membrane reactor in which both reaction and separation occur at a same time. Especially, in the case of hydrogen production catalyst, hydrogen separation, and the membrane reactor coupled with catalyst and separation, extensive results have been reported on the effect of the dopant in the solid electrolytes, temperature, and composition of reactants on the performance. In this review, the recent research trend on the application of proton-conducting ceramic materials to hydrogen production catalyst, hydrogen separation, and membrane reactor is surveyed. Moreover, the potential application and prospect of these materials to the next-generation hydrogen production and separation is discussed.

• Membrane Journal
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• v.14 no.4
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• pp.329-338
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• 2004

In this study the discharged wastewater from paper manufacturing plant was filtrated by 4 kinds of tubular ceramic microfiltration and ultrafiltration membranes (carbon material) with periodic water-back-flushing, and we tried to find the optimum back-flushing time (BT). As results of water-BT effect for each ceramic membrane, the longer BT was more effective for a membrane having the larger pore size. And we could acquire the most volume of total permeate and the highest recovery efficiency of purified water, Then, the results of permeate flux vs. initial permeate flux during 180 min's operation showed that the longer BT was more effective for longer filtration time (FT) to obtain the higher permeate flux because membrane fouling proceeded deeply at long FT condition. And the optimum BT that founded from the trends of membrane fouling resistances almost accorded with the optimum BT from the trends of permeate flux, too.

• Membrane Journal
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• v.27 no.6
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• pp.469-476
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• 2017

Membrane separation is a technology of low energy consumption. Membranes made of zeolites are of great interest because their fixed and open pores in the size of small molecules inside crystalline structures allow separation processes under harsh conditions. While zeolite NaA (LTA-type) is industrially used for dewatering of organic solvents, its pore size and thermal and hydrothermal stability can be tuned by exchange of framework and extra-framework elements. SOD with pores of only 0.28 nm is of great interest for $H_2$- und $H_2O$-separation and also can be tuned by ion exchange. Zeolites open the opportunity to create membranes of adapted separation behavior for small molecules in conditions of surrounding technical processes.

• Journal of Korean Society of Water and Wastewater
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• v.32 no.2
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• pp.77-87
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• 2018

In this study, the effects of operating conditions on the formation of reversible and irreversible fouling were investigated in the filtration using ceramic membrane for water treatment process. The effect of coagulation pretreatment on fouling formation was also evaluated by comparing the performance of membrane filtration both with and without addition of coagulant. A resistance-in-series-model was applied for the analysis of membrane fouling. Total resistance (RT) and internal fouling resistance (Rf) increased in the membrane filtration process without coagulation as membrane flux and feed water concentrations increased. Internal fouling resistance, which was not recovered by physical cleaning, was more than 70% of the total resistance at the range of the membrane flux more than $5m^3/m^2{\cdot}day$. In the combined process with coagulation, the cake layer resistance (Rc) increased to about 30-80% of total resistance. As the cake layer formed by coagulation floc was easily removed by physical cleaning, the recovery rate by physical cleaning was 54~90%. It was confirmed from the results that the combined process was more efficient to recover the filtration performance by physical cleaning due to higher formation ratio of reversible fouling, resulted in the mitigation of the frequency of chemical cleaning.

• Applied Chemistry for Engineering
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• v.24 no.4
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• pp.433-437
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• 2013

Electrical discharge plasma created in a multi-channel porous ceramic membrane-supported catalyst was applied to the decomposition of a volatile organic compound (VOC). For the purpose of improving the oxidation capability, the ceramic membrane used as a low-pressure drop catalyst support was loaded with zinc oxide photocatalyst by the incipient wetness impregnation method. Alternating current-driven discharge plasma was created inside the porous ceramic membrane to produce reactive species such as radicals, ozone, ions and excited molecules available for the decomposition of VOC. As the voltage supplied to the reactor increased, the plasma discharge gradually propagated in the radial direction, creating an uniform plasma in the entire ceramic membrane above a certain voltage. Ethylene was used as a model VOC. The ethylene decomposition efficiency was examined with experimental variables such as the specific energy density, inlet ethylene concentration and zinc oxide loading. When compared at the identical energy density, the decomposition efficiency obtained with the zinc oxide-loaded ceramic membrane was substantially higher than that of the bare membrane case. Both nitrogen and oxygen played an important role in initiating the decomposition of ethylene. The rate of the decomposition is governed by the quantity of reactive species generated by the plasma, and a strong dependence of the decomposition efficiency on the initial concentration was observed.

• Membrane and Water Treatment
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• v.6 no.6
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• pp.477-488
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• 2015

This study demonstrates that low pressure membranes are the ideal choice for industrial and/or municipal wastewater treatment by showing some promising experimental results, understanding different membrane filtration models, studying the potential of membrane bioreactors (MBRs), considering ceramic membranes fabrication and illustrating the role of nanotechnology in membranes. Cost study calculations are included to determine the treatment cost as well as the initial cost of various membrane types. Results showed that integrated membranes are preferred over MBR in case of average capacities. However, higher capacity situations are the most economical choice for MBR. It is shown that the least treatment cost in MBR was about $0.13/m^3$. However, the $0.13/m^3$ is the theoretical cost which is very small compared to the actual average MBR treatment cost of $0.5/m^3$.

• Membrane and Water Treatment
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• v.10 no.6
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• pp.431-440
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• 2019

A novel composite membrane was synthesized using crosslinked polyamide and fly ash ceramic substrate for phenol removal. Glutaraldehyde was used as crosslinker. Characterization shows that synthesized membrane possesses good permeability ($0.184l.m^{-2}.h^{-1}.kPa^{-1}$), MWCO (1.7 kDa), average pore size (1.08 nm) and good chemical stability. RSM was adopted for phenol removal studies. Box-Behnken-Design using quadratic model was chosen for three operating parameters (feed phenol concentration, pH and applied pressure) against two responses (phenol removal, flux). ANOVA shows that model is statistically valid with high coefficient of determination ($R^2$)value for flux (0.9897) and phenol removal (0.9302). The optimum conditions are obtained as pH 2, $46mg.l^{-1}$ (feed phenol concentration) and 483 kPa (applied pressure) with 92.3% phenol removal and $9.2l.m^{-2}.h^{-1}$ flux. Data validation with deviation of 4% confirms the suitability of model. Obtained results reveal that prepared composite membrane can efficiently separate phenol from aqueous solution.

• Proceedings of the Membrane Society of Korea Conference
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• 2001.05a
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• pp.116-119
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• 2001

• Proceedings of the Membrane Society of Korea Conference
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• 1999.04a
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• pp.75-77
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• 1999

• Proceedings of the Membrane Society of Korea Conference
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• 1999.04a
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• pp.78-80
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• 1999