Studies on ion-isotopic exchange reactions using nuclear grade ion exchange resins

2013

ILCPA

Nondestructive radioanalytical technique using short lived isotopes 131 I and 82 Br was used as tracers to study the kinetics of iodide and bromide ion-isotopic exchange reactions. The kinetic data so obtained was used to evaluate the performance of organic base anion exchange resins Purolite NRW-6000 and Duolite A-378. It was observed that for iodide ion-isotopic exchange reaction performed at 40.0 °C using 1.000 g of ion exchange resins and 0.003 mol/L labeled iodide ion solution, 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 0.332, 0.582, 0.193 and 16.2 respectively for Purolite NRW-6000 resin, which was higher than the respective values of 0.210, 0.421, 0.088 and 14.7 as that obtained for Duolite A-378 resins. Also at a constant temperature of 40.0 °C, as the concentration of labeled iodide ion solution increases from 0.001 mol/L to 0.004 mol/L, the percentage of iodide ions exchanged increases from 74.68 % to 79.48 % using Purolite NRW-6000 resins and from 52.30 % to 58.90 % using Duolite A-378 resins. The overall results indicate superior performance of Purolite NRW-6000 resins over Duolite A-378 resins under identical operational parameters. It is expected here that the present technique can be extended further for characterization of different ion exchange resins which will further help in the selection of those reins for the specific industrial application.

Section: Comparative Study Of Ion-isotopic Exchange Reactionsmentioning

confidence: 98%

Section: Study On Kinetics Of Iodide Ion-isotopic Exchange Reactionmentioning

confidence: 99%

Radio Analytical Nondestructive Technique in Performance Evaluation of Organic Base Ion Exchange Resins Purolite NRW-6000 and Duolite A-378

2013

ILCPA

“…The iodide ion-isotopic exchange reaction can be represented as: The activity of solution was measured at a fixed interval of every 2.0 min. The final act ivity (A f ) of the solution was also measured after 3h wh ich was sufficient time to attain the equilibriu m [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30]. The activ ity measured at various time intervals was corrected for background counts.…”

Section: Study On Kinetics Of Iodi De Ion-isotopic Exchange Reactionmentioning

confidence: 99%

Comparative Study of Strongly Basic Anion Exchange Resins Tulsion A-30 and Indion-820 by Application of 131I and 82 Br as a Tracer Isotopes

2013

CMATERIALS

In the present investigation radioactive tracer isotopes 131 I and 82 Br were used to study the kinetics of iodide and bromide ion-isotopic exchange reaction. The kinetics study was performed to study the effect of ionic concentration and temperature on the specific reaction rate calculated in min -1 . Fro m the initial ionic concentration and knowing the value of specific reaction rate, the values of amount of ions exchanged in mmo l and percentage ion exchange were calcu lated. It was also observed that for both the resins, there exists strong positive co-relat ionship between amount of ions exchanged and concentration of ionic solution, while a strong negative co-relationship was observed between amount of ions exchanged and temperature of exchanging mediu m. The values of specific reaction rate, amount and percentage of ions exchanged so obtained for the ion-isotopic exchange reactions using strong base, nuclear grade anion exchange resin Tulsion A-30 and non-nuclear grade anion exchange resin Indion-820 were co mpared. It was observed that the above values calculated were higher for Tulsion A-30 as compared to that for Indion-820, indicating superior performance of Tu lsion A-30 under identical experimental conditions. The similar study on application of radioactive tracer isotopes can be extended further for performance assessment of different nuclear as well as non-nuclear grade ion exchange resins.

“…The final activity (A f ) of the solution was also measured after 3h wh ich was sufficient time to attain the equilibriu m [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26]. The activ ity measured at various time intervals was corrected for background counts.…”

Section: Study On Kinetics Of Iodi De Ion-isotopic Exchange Reactionmentioning

confidence: 99%

“…Preliminary studies show that the above exchange reactions are of first order [27,28]. Therefore logarith m of activity when plotted against time gives a co mposite curve in which the activity initially decreases sharply and thereafter very slowly giving nearly straight line (Figure 1), evidently rapid and slow ion-isotopic exchange reactions were occurring simu ltaneously [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26]. Now the straight line was extrapolated back to zero time.…”

Section: Comparati Ve Study Of Ion-isotopic Exchange Reactionsmentioning

confidence: 99%

Comparative Study of Duolite A-378 and Duolite A-143 Anion Exchange Resins by Application of 131I and 82 Br as a Tracer Isotopes

2012

CHEMISTRY

In the present study radioactive tracer isotopes 131 I and 82 Br are applied to study the kinetics of iodide and bromide ion-isotopic exchange reactions in two anion exchange resins Duolite A-378 and Duolite A-143. The study is performed by varying the experimental parameters like temperature and concentration of exchanging mediu m to understand the effect of above parameters on exchange reaction rate (min -1 ), amount of ions exchanged (mmol), percentage of ions exchanged and distribution coefficient. For both the ion-isotopic exchange reactions it is common observation that the exchange reaction rate increases with increase in concentration and decreases with rise in temperature of exchanging med iu m. Also there exists a strong positive co-relationship between amount of ions exchanged and concentration of ionic solution, while a strong negative co-relationship exists between amounts of ions exchanged and temperature of exchanging mediu m. Co mparing the values of reaction rate (min -1 ), amount of ions exchanged (mmol); percentage of ions exchanged and distribution coefficient calculated for the two resins, it is observed that Duolite A-378 resins show superior performance than Duolite A-143 resins under identical operational parameters.