• Nuclear Engineering and Technology
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• v.40 no.6
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• pp.489-496
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• 2008

Ferrocyanide-anion exchange resin was prepared and the prepared ion exchange resins were tested on the ability to uptake $Cs^+$ ion. The prepared ion exchange resins were resin-KCoFC, resin-KNiFC, and resin-KCuFC. The three tested ion exchange resins showed ion exchange selectivity on the $Cs^+$ ion of the surrogate soil decontamination solution, and resin-KCoFC showed the best $Cs^+$ ion uptake capability among the tested ion exchange resins. The ion exchange behaviors were explained well by the modified Dubinin-Polanyi equation. A regeneration feasibility study of the spent ion exchange resins was also performed by the successive application of hydrogen peroxide and hydrazine. The desorption of the $Cs^+$ ion from the ion exchange resin satisfied the electroneutrality condition in the oxidation step; the desorption of the $Fe^{2+}$ ion in the reduction step could also be reduced by adding the $K^+$ ion.

• Nuclear Engineering and Technology
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• v.46 no.1
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• pp.93-100
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• 2014

The paper deals with the application of radio isotopic non-destructive technique in the characterization of two industrial grade anion exchange resins Indion GS-300 and Indion-860. For the characterization of the two resins, $^{131}I$ and $^{82}Br$ were used as tracer isotopes to trace the kinetics of iodide and bromide ion-isotopic exchange reactions. It was observed that the values of specific reaction rate ($min^{-1}$), amount of iodide ion exchanged (mmol), initial rate of iodide ion exchange (mmol/min) and log $K_d$ were calculated as 0.328, 0.577, 0.189 and 19.7 respectively for Indion GS-300 resin, which was higher than the respective values of 0.180, 0.386, 0.070 and 17.0 calculated for Indion-860 resins when measured under identical experimental conditions. Also at a constant temperature of $40.0^{\circ}C$, as the concentration of labeled iodide ion solution increases 0.001 M to 0.004 M, the percentage of iodide ions exchanged increases from 75.16 % to 78.36 % for Indion GS-300 resins, which was higher than the increases from 49.65 % to 52.36 % compared to that obtained for Indion-860 resins. The overall results indicate that under identical experimental conditions, Indion GS-300 resins show superior performance over Indion-860 resins.

• Nuclear Engineering and Technology
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• v.53 no.9
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• pp.2918-2925
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• 2021

The efficiency of decontamination of model spent ion exchange resins, contaminated with magnetite and hematite, with mineral acid solutions, and using electro-decontamination, was evaluated. It has been shown that effective hematite dissolution occurs in concentrated mineral acid solutions. However, the use of direct current increases the decontamination efficiency of spent ion exchange resins contaminated with hematite. It is determined that with increasing voltage and acid concentration, the dissolution efficiency of hematite deposits increases and can exceed 99%. It has been shown that hematite dissolution is accompanied by secondary adsorption of radionuclides due to ion exchange, which can be removed with sodium nitrate solutions.

• Applied Chemistry for Engineering
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• v.1 no.1
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• pp.23-29
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• 1990

The effect of a rapid freeze pretreatment of organic ion exchange resins on their grinding properties was studied. It was found that the structure of ion exchange resins was defected by freezing pressure formed in the process of rapid freezing. The defected resins didn't recover their own structure after thawing and those could be easy to be broken at room temperature by small force. Therefore, organic ion exchange resins could be ground readily at room temperature after rapid-freezing the fully swelled resins using by solid carbon dioxide, or liquid nitrogen. The rapid freeze pretreatment of cation exchange resins was very effective on grinding in particular. However, the effect of the pretreatment of anion exchange resins on grinding was less than that of cation exchange resins. In case of anion exchange resins, the ionic form of affected the grindability remarkably.

• Membrane Journal
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• v.34 no.2
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• pp.132-139
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• 2024

The ion exchange resin used to remove total dissolved solids (TDS) is used by being packed in a column, and sufficient contact time between the ionic material and the ion exchange resin is required during the ion exchange process. In this study, the ion exchange resin that exhibits high TDS reduction even with a short contact time through pulverization of the ion exchange resin was characterized. The optimal size of resin considering flowability was over 100 ㎛. The highest pulverizing yield were obtained that 250~500 ㎛ size and 100~250 ㎛ size were 67.3% and 36.9%, respectively. Also, the highest yield and the pulverizing time of 100~500 ㎛ size was 87.1% and 2 minutes, respectively. Under batch test conditions, the time to reach a removal rate of 95% and 99% for 250~500 ㎛ resins was 1.82 and 1.96 times faster than non-pulverized ion exchange resin, respectively. The 100~250 ㎛ resins showed 15.9 times and 6.18 times faster, respectively. Under the column test, a total of 1.74 g of NaCl was removed by non-pulverized ion exchange resins, 1.83 g of NaCl was removed by 250~500 ㎛ resins and 1.63 g of NaCl was removed by 100 and 250 ㎛ resins. As the size of the resin decreased, the capacity slightly decreased. As a result, it was observed that the pulverized ion exchange resins could be a method of achieving high TDS removal performance under short contact time.

• Journal of environmental and Sanitary engineering
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• v.15 no.4
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• pp.114-122
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• 2000

Several new ion exchange resins have been synthesized from chloromethyl styrene-1,4-divinylbenzine with 1%, 2%, 5% and 105-crosslink and macrocyclic ligands of cryptand type by interpolymerization method. The adsorption characteristics and the pH, time, solvents and concentration dependence of the adsorption of uranium ion by this resins were studied. The resins were very stable in both acidic and basic media and have good resistance to heat at $300^{\circ}C$. The uranium ion are not adsorbed on the resins below pH 3.0, but the power of adsorption of it increased rapidly above pH 4.0. The optimum equilibrium time for adsorption of uranium ion was two hours and adsorptive power decreased in proportion to crosslink size of the resins and order of dielectric constants of solvents used and the adsorption for uranium ion was bin the order of $OdienNtn-H_4$ > $OtnNen-H_4$ > $OtnNen-H_4$ > $OenNen-H_4$.

• Journal of the Korean Chemical Society
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• v.3 no.1
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• pp.18-22
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• 1954

The cation exchange resins are synthesized from p-phenolsulfonic acid, formalin, and sodium hydroxide catalyser, and the ion exchange properties of them are studied with respect to their reactant ratios. Maximum exchange capacity was 2.06 me/G, much smaller than the theoretical value of 3.42 me/G to be expected for that of the structure: Under the present experimental conditions, much -SO3H radical should have been split away.

• Journal of Korean Society on Water Environment
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• v.29 no.6
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• pp.777-781
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• 2013

Ion-exchange technology is one of the best for removing nitrate from drinking water. However, problems related to the disposal of spent brine from regeneration of exhausted resins must be overcome so that ion exchange can be applied more widely and economically, especially in small communities. In this background, a combined bio-regeneration and ion-exchange system was operated in order to prove that nitrate-laden resins could be bio-regenerated through direct contact with denitrifying bacteria. A nitrate-selective A520E resin was successfully regenerated by denitrifying bacteria. The bio-regeneration efficiency of nitrate-laden resins increased with the amount of flow passed through the ion-exchange column. When the fully exhausted resin was bio-regenerated for 5 days at the flowrate of 30 BV/hr and MLSS concentration of $125{\pm}25mg/L$, 97.5% of ion-exchange capacity was recovered. Measurement of nitrate concentrations in the column effluents also revealed that less than 5% of nitrate was eluted from the resin during 5 days of bio-regeneration. This result indicates that the main mechanism of bio-regeneration is the direct reduction of nitrate by denitrifying bacteria on the resin.

• Korean Journal of Materials Research
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• v.26 no.9
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• pp.498-503
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• 2016

The characteristics of aqueous lithium recovery by ion exchange were studied using three commercial cation exchange resins: CMP28 (porous type strong acid exchange resin), SCR-B (gel type strong acid exchange resin) and WK60L (porous type weak acid exchange resin). CMP28 was the most effective material for aqueous lithium recovery; its performance was even enhanced by modifying the cation with $K^+$. A comparison to $Na^+$ and $H^+$ form resins demonstrated that the performance enhancement is reciprocally related to the electronegativity of the cation form. Further kinetic and equilibrium isotherm studies with the $K^+$ form CMP28 showed that aqueous lithium recovery by ion exchange was well fitted with the pseudo-second-order rate equation and the Langmuir isotherm. The maximum ion exchange capacity of aqueous lithium recovery was found to be 14.28 mg/g and the optimal pH was in the region of 4-10.

• Journal of the Korean Electrochemical Society
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• v.18 no.1
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• pp.24-30
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• 2015

To desalinate the aqueous solutions with high salt concentration using the capacitive deionization technology, two resin/membrane capacitive deionization(RMCDI) cells were fabricated by filling mixed ion exchange resins in two different flow channels (spacer and spiral type). The salt removal efficiency of the spacer- and spiral-RMCDI was 77.21 and 99.94%, respectively. Many ions were significantly removed in a spiral RMCDI cell because the feed solution could be more evenly contacted with the ion exchange resins filled on the spiral type flow channel. As the result of the changes of pH and accumulative charges, it was observed that Faradaic reaction was diminished for a spiral RMCDI cell filled by the mixture of cation and anion exchange resins. Therefore, the desalination of the aqueous solutions with high salt concentration by the capacitive deionization technology was proven. In addition, further studies on the optimization of the mixing ratio with ion exchange resins and the introduction of the regeneration process generally occurred in the continuous electrodeionization (CEDI) technology are required to improve the RMCDI technology.