• Polymer(Korea)
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• v.31 no.3
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• pp.247-254
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• 2007

Heterogeneous anion exchange membranes were prepared by compression molding for the recovery of sulfate ion from waste water. The swelling ratio, transport number, and ion exchange capacity of the heterogeneous anion exchange membranes were increased and their electrical resistances were decreased as the amount of ion exchange resin content in the matrix was raised. The tensile strength of the heterogeneous anion exchange membrane was decreased with increasing the amount of ion exchange resin in the LLDPE. The tensile strength for the LDPE heterogeneous membrane containing 30 wt% anion exchange resin showed the highest value. The water content increased with increasing amount of ion exchange resin in the membrane. Moreover the highest transport number of the membrane was 0.86. The electrical resistance of LDPE matrix membrane with 50 wt% resin showed $46.5{\Omega}{\cdot}cm^2$. Current efficiency of electrodialysis for sulfate ion showed the highest value at the current density of $125 mA/cm^2$ in 0.5 mol/L sulfuric acids solution.

• Applied Chemistry for Engineering
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• v.26 no.1
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• pp.1-16
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• 2015

In this review, we summarized some of membrane processes using the ion exchange membrane typically used in energy applications. Ion exchange membranes are classified according to their functions, formations (e.g. heterogeneous, homogeneous), and polymer type. Furthermore, various methods to prepare cation exchange membranes and anion exchange membranes were discussed in detail and also illustrated through a thorough review of the literature works. There are numerous reports highlighting recent research trends in the ion exchange membrane fabrication, however, in this review we will focus more on discussing the development made in ion exchange membranes and their potential usages in future technologies.

• Korean Chemical Engineering Research
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• v.57 no.1
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• pp.65-72
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• 2019

In this study, heterogeneous ion exchange membranes were prepared by casting method with various mixing ratios of PPO ion-selective solution and ion exchange resin. Then heterogeneous bipolar membranes were prepared by using this. The water content of heterogeneous cation and anion exchange membranes were 60~80% respectively, the ion exchange capacity was 2.81~3.26 meq/g, 2.31~2.74 meq/g and electrical resistances were $1.65{\sim}1.45{\Omega}{\cdot}cm^2$ and $1.55{\sim}1.05{\Omega}{\cdot}cm^2$. The tensile strength of heterogeneous bipolar membrane was lower than that of PPO resin before functionalization ($700Kg_f/cm^2$). The tensile strength of heterogeneous bipolar membrane with catalyst layer was lower than that of non-catalytic heterogeneous bipolar membrane. The water splitting voltage of the heterogeneous bipolar membrane with catalyst layer was low and stable at a minimum of 1.7~1.8 V, maximum 3.9~4.0 V, and the water splitting voltage of the non-catalytic heterogeneous bipolar membrane was constant at 3.8~4.0 V.

• Membrane Journal
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• v.27 no.1
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• pp.84-91
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• 2017

In this study, heterogeneous ion exchange membranes were prepared by mixing cation or anion exchange resins and commercial polyvinylidene fluoride (PVDF) for MCDI process. The mixing ratios of PVDF and ion exchange resins were 1 : 1, 1.4 : 1, 2 : 1, and 3 : 1. We characterized SEM, water content, ion exchange capacity, methanol permeability, and ion conductivity. In the viewpoint of membrane characterization, the blending ratio of 2 : 1 showed the best. For the blending ratio of 2 : 1, heterogeneous cation exchange membrane showed the water content 34%, ion exchange capacity 1.54 meq/g, ion conductivity 0.019 S/cm, and methanol permeability $2.28{\times}10^{-7}{\sim}8.86{\times}10^{-7}cm^2/s$ while In the case of heterogeneous anion exchange membrane, the result showed 37%, 2.18 meq/g, and 0.034 S/cm and $1.46{\times}10^{-7}{\sim}8.66{\times}10^{-7}cm^2/s$.

• Korean Journal of Materials Research
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• v.8 no.11
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• pp.1061-1066
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• 1998

The synthesises of anion exchange resin from 4vinylpyridine-divinyIbenzene(4-VP-DVB) were intented to separate boron ion. The heterogeneous anion exchange membranes were prepared with polyethylene(PE) matrix bythe hot press method. The prepared exchange membranes were characterized by FT-IR, conductormeter and pH meter to confirm structural, mechanical and electrochemical properties. Their capacities were measured by changing floe rate and voltage. The best seperation capacity was appeared in the heterogeneous membrane which contains 50 wt % 4-VP-DVB resin within PE matrix. The heterogeneous membranes treated with acid were better than that treated with water. Results from this experiment were indicated that the optimal flow rate, voltage. and time in the seperation of boron ion were lOml/min, 18volts, and 4 hours respectively.

• Membrane Journal
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• v.27 no.3
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• pp.240-247
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• 2017

In this study, the heterogeneous ion exchange membranes prepared by the combination of the carbon electrode and mixed the cation and anion exchange polymers and polyvinylidene fluoride as the basic polymer together were made to recognize the efficiency of the salt removal for the application of the membrane capacitive deionization process. The mixing weight ratio of the solvent, basic polymer and ion exchange resin was 7 : 2 : 1 and this mixed solution was directly cast on the electrode. As for the operating conditions of the adsorption voltage and time, feed flow rate, desorption voltage and time of the feed solution NaCl 100 mg/L, the salt removal efficiencies (SRE) were measured. Apart from this NaCl, the $CaCl_2$ and $MgSO_4$ solutions were investigated in terms of SRE as well. Typically, SRE for NaCl 100 mg/L solution under the conditions of adsorption voltage/time, 1.5 V/3 min, desorption voltage/time -0.1 V/3 min, was shown 98%. And for the $CaCl_2$ and $MgSO_4$ solutions, the SREs of 70 and 59% were measured under the conditions of adsorption voltage/time, 1.2 V/3 min, desorption voltage/time -0.5 V/5 min, respectively.