• 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.

• 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.

• Applied Chemistry for Engineering
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• v.27 no.6
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• pp.633-638
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• 2016

In this study, we used three kinds of commercially available cation, anion, and mixed-ion exchange resins to separate radioactive ions from a polluted water containing Cs, I, and other radioactive ions. The experiment was conducted at a room temperature with a batch method, and a comparative analysis on the decontamination ability of each resin for the removal of Cs and I was performed by using different quantities of resins. The concentration was analyzed using ion chromatography and the ion exchange resin product from company D showed an overall high ion exchange ability. However, for most of the experiments when the amount of ion exchange resin was decreased, the decontamination ability of the resins against mass increased. When the mass of company D's cation exchange resin was small, the ion exchange ability against Cs and I ions were measured as 0.199 and 0.344 meq/g, respectively. When the mixed ion exchange resin was used, the ion exchange ability against I ions was measured as 0.33 meq/g. All in all, company D's ion exchange resins exhibited a relatively higher ion exchange ability particularly against I ions than that of other companies' exchange ions.

• Applied Chemistry for Engineering
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• v.23 no.1
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• pp.86-92
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• 2012

A characteristic study of chlorine dioxide generation by the electrolysis system was performed after chlorite ($ClO_2^-$) is adsorbed from sodium chlorite by a polymer ion exchange resin. A strongly basic anion exchange resin was used and a Ti plate coated with Ru and Ir was used as an electrode. Various parameters such as reaction stirring velocity, reaction temperature, chlorine dioxide product concentration, ion exchange resin content and product maker type for the adsorption quantity in the chlorite adsorption of ion exchange resin were investigated and found the ion exchange resin with the maximum adsorption quantity. A generation trend of chlorine dioxide was observed by the electrolysis system and optimum conditions on the desired value were found using response surface design of DOE (Design of Experiments). The strongly basic anion exchange resin with the maximum adsorption quantity was SAR-20 (TRILITE Gel type II) and the adsorption quantity was around 110 mg/IER (g). Observed generation optimum conditions of chlorine dioxide were constant-current (electrode area base; $A/dm^2$) and flow rate of $N_2$ gas (4.7 L/min) at the desired value of sterilization (900~1000 ppm, 1 h).

• Journal of Pharmaceutical Investigation
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• v.29 no.4
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• pp.309-313
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• 1999

This study was prepared to develop the sustained release dosage form of phenylpropanolamine hydrochloride (PPA) by complexation with cation exchange resin(CER). The PPA-CER complex was confirmed by differential scanning calorimetry(DSC) thennogram, indicating a relative shift of an endometric peak of PPA to higher temperature. The loading efficiency was increased as the amount of PPA was increased as well as the time of fractional exchange was advanced as the temperatures were increased. Loading efficiency, fractional exchange, reaction rate constant and activation energy were highly dependent on the temperature and drug : resin ratio. The optimal ratio of PPA and resin was estimated to be 10: 10 for the sustained release.

• Journal of Environmental Science International
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• v.11 no.3
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• pp.263-269
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• 2002

This study was conducted to know the removal characteristics of ammonia nitrogen by commercially available cation exchange resins. Eight acidic cation exchange resins were investigated in batch reactors. Among them, the most effective resin for ammonia removal in solution was PK228, which was a strong acidic resin of $Na^{+}$ type. PK228 was compared with activated carbon and natural zeolite. The effects of cation exchange capacity, ammonia concentration, resin amount, temperature and pH on ammonia removal by PK228 were investigated in batch reactor, and the effect of effluent velocity in continuous column reactor. Strong acidic resins of porous type were more effective than week acidic resins or gel type resins for ammonia removal in solution. PK228 was more effective than activated carbon and natural zeolite for ammonia removal in batch reactor. With increasing initial ammonia concentration, the amount of ammonia removed by PK228 increased, but the proportion of removed ammonia to initial ammonia concentration decreased. The effect or temperature on ammonia removal by PK228 was very slight. The ammonia removal to acidic solution was more effective than that at basic solution. With decreasing effluent velocity of solution through column, breakthrough point extended, and ammonia removal capacity increased.d.

• Applied Chemistry for Engineering
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• v.10 no.1
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• pp.51-57
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• 1999

Adsorption characteristics of Ni(II), Co(II) and Ag(I) ions on the Amberite IRN 77 cation exchange resin have been studied to suggest the guide-line for the optimum operation of demineralization process in primary coolant system during the shut-down period of pressurized water reactor(PWR). The adsorption mechanism of each metal ion, Ni(II), Co(II) or Ag(I) ion, on a cation exchange resin was well coincided with Langmuir isotherm. The adsorption and treatment capacities of $H^+$-form resin were higher than those of $Li^+$-form resin. In the continuous ion exchange process for the solution of multi-component system, the selectivity of the resin was in increasing order of Ni(II)${\approx}$Co(II)>Ag(I). In addition, the increase of the flow rate decreased the treatment capacity of the resin as well as the slope of the breakthrough curve.

• Membrane and Water Treatment
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• v.3 no.4
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• pp.211-219
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• 2012

To enhance the efficiency of water treatment and reduce the extent of membrane fouling, the membrane separation process is frequently preceded by other physico-chemical processes. One of them might be ion exchange. The aim of this work was to compare the efficiency of natural organic matter removal achieved with various anion-exchange resins, and to verify their potential use in water treatment prior to the ultrafiltration process involving a ceramic membrane. The use of ion exchange prior to ceramic membrane ultrafiltration enhanced final water quality. The most effective was MIEX, which removed significant amounts of the VHA, SHA and CHA fractions. Separation of uncharged fractions was poor with all the resins examined. Water pretreatment involving an ion-exchange resin failed to reduce membrane fouling, which was higher than that observed in unpretreated water. This finding is to be attributed to the uncharged NOM fractions and small resin particles that persisted in the water.

• Membrane and Water Treatment
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• v.13 no.1
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• pp.1-6
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• 2022

The regulations of the International Maritime Organization (IMO) have been steadily strengthened in ship emissions. Accordingly, there is a growing need for development of related technologies for the removal of contaminants that may occur during the treatment of SOx and NOx using a wet scrubber. However, this system also leads to wastewater production when the exhaust gas is scrubbed. In this research, we evaluated the performance of an ion selective resin process in accordance with scrubber wastewater discharge regulations, specifically nitrate discharge, by the IMO. Accelerated real and synthetic wastewater of wet scrubbers, contained high amounts of TDS with high nitrate, is used as feed water in lab scale systems. Furthermore, a pilot scale dissolved air flotation (DAF) using microbubble generator with ion exchange resin process was combined and developed in order to apply for the treatment of wet scrubber wastewater. The results of the present study revealed that operating conditions, such as resin property, bed volume (BV), and inlet wastewater flow rate, significantly affect the removal performance. Finally, through a pilot test, DAF with ion exchange resin process showed a noticeable improvement of the nitrate removal rate compared to the single DAF process.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.54-55
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• 2018

Reinforced concrete is a building material that is generally used in modern society. Securing the performance of reinforced concrete is directly connected to the durability and longevity of the building. One of the major factors that deteriorate the durability of concrete is harmful ion. Recently, the quality and improvement method of reinforced concrete for penetration of harmful ion has been studied. In this study, the bead type ion exchange resin is substituted for 0%, 3%, and 6% of the fine aggregate volume in the mortar. The speciments underwent underwater curing and were checked for compressive strengths of 3 days and 28 days. From the results of compressive strength, it can be seen that the higher the substitution ratio of the ion exchange resin, the lower the early strength and long-term strength development, especially the early strength development.