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Comparative study of indium-810 and indium-454 strongly basic anion exchange resins with ~ (131) I and ~ (82) Br as tracer isotopes

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https://www.eduzhai.net International Journal of M aterials and Chemistry 2012, 2(4): 151-157 DOI: 10.5923/j.ijmc.20120204.07 Comparative Study of Indion-810 and Indion -454 Strongly Basic Anion Exchange Resins by Application of 131I and 82 Br as a Tracer Isotopes Pravin U. Singare Department of Chemistry, Bhavan’s College, M unshi Nagar, Andheri (West), M umbai, 400 058, India Abstract The present investigation deals with application of radiotracer isotopes 131I and 82Br for performance assessment of industrial grade strongly basic anion exchange resins Indion-810 and Indion -454. The study reveals the higher percentage of ions exchanged by Indion -454 resins as compared to Indion-810 under identical e xperimental conditions. It is observed that iodide ions are exchanged at the faster rate than bromide ions; however the exchange rate decreases with rise in temperature and increases with increase in ionic concentration. The study indicates strong positive correlat ion between amount of ions exchanged and concentration of ionic solution, and a strong negative correlation between amount of ions exchanged and temperature of the exchanging solution. Keywords Radiotracer Isotopes, 82Br, 131I, Ion-Isotopic Exchange, Reaction Kinetics, Ion Exchange Resins, Indion-810, Indion -454 1. Introduction Ion-e xchange resins are produced and commerc ialized in a wide range of formu lat ions with d ifferent characteristics, and have now a large pract ical applicability in various industrial processes, such as chemical, nuclear, pharmaceutical, food industry, etc. Nowadays, ion exchange resins are not only used for separation but also used as a catalyst. In the past decade inorganic ion exchange materials have emerged as an in creas ing ly impo rtant rep lacement o r co mp lement for convent ion al org an ic ion exchang e res ins . Ho wever in number of cases, for specific physical and che mica l reasons, organic res ins cannot be replaced by inorganic ion exch ang ers and o rg an ic ion exch ang e res ins co nt in ue globally in various industrial applications[1-3]. Therefo re develop ment of new o rgan ic ion exchange materials for specific industrial and technological applications is a biggest challenge to present day researchers. Develop ment of ion exchange resins is usually followed by characterization to understand the p erfo rmance o f those res ins in various technological applications. Although number of techniques are available for the characterization of ion exchange resins, but the radiotracer technique offer several advantages such as high detection sensitivity, capability of in-situ detection, limited memory effects and physic-chemical co mpatib ility * Corresponding author: pravinsingare@gmail.com (Pravin U. Singare) Published online at https://www.eduzhai.net Copyright © 2012 Scientific & Academic Publishing. All Rights Reserved with the material under study. There are two main reasons for the continuing interest in application of radiotracer technique. Firstly, it is industry driven. Because of their unique properties, radioactive isotopes can be used to obtain information about plants and processes that cannot be obtained in any other way. Often, the information is obtained with the plant on-stream and without disrupting the process in any way. This can lead to substantial economic benefits, fro m shutdown avoidance to process optimization. Secondly, the methodology is derived fro m many fields of science and technology including radioisotope production, radiation detection, data acquisition, treatment and analysis, and mathematical modelling. The fundamental principle in radiochemica l investigations is that the chemical properties of a rad ioisotope of an element are almost the same as those of the other stable/radioactive isotopes of the element. When radioisotope is present in a chemical form identical to that of the bulk of the element in a chemical process, then any reaction the element undergoes can be directly traced by monitoring the radioisotope. Radio isotope can also be tagged to a molecule or material to follow a process. Radiochemical work involves two main steps first is the sampling of chemical species to be studied and second is quantitative determination of the radiation emitted by the radioisotope in the sample[4]. Radiotracer methodology is described extensively in the literature[5]. Applications of radiotracers in chemical research cover the studies of reaction mechanism, kinetics, exchange processes and analytical applications such as radio metric titrat ions, solubility product estimation, isotope dilution analysis and autoradiography. 152 Pravin U. Singare: Comparative Study of Indion-810 and Indion -454 Strongly Basic Anion Exchange Resins by Application of 131I and 82 Br as a Tracer Isotopes Hence in the present investigation, radiotracer isotopes are applied to assess the performance of industrial grade ion exchange resin under different experimental conditions like temperature and concentration of ionic species present in the external exchanging med iu m. 2. Experimental 2.1. Condi tioni ng of Ion Exchange Resins Ion exchange resins Indion-810 and Indion-454 (by Ion Exchange India Ltd., Mu mbai) are strongly basic anion exchange resin in chloride form having quaternary ammon iu m -N+R3 functional group. Details regarding the properties of the resins used are g iven in Table 1. These resins were converted separately in to iodide / bro mide form by treatment with 10 % KI / KBr solution in a conditioning column which is adjusted at the flow rate as 1 mL / min. The resins were then washed with double distilled water, until the washings were free fro m iodide/bro mide ions as tested by AgNO3 solution. These resins in bromide and iodide form were then dried separately over P2O5 in desiccators at room temperature. Table 1. Propert ies of ion exchange resins Ion exchange resin Matrix Particle Size (mm ) Moisture content (%) Operating pH Maximum operating Temperature (°C) Total exchange capacity Indio Crosslinked 0.3-0.1 n-810 Polystyrene 2 53 0-14 60 1.10 meq./ mL Indio Crosslinked n-454 Polystyrene ≤0.15 ≤10 0-14 60 3.80 meq./ g 2.2. Radioacti ve Tracer Isotopes The radioisotope 131I and 82Br used in the present experimental work was obtained fro m Board of Radiation and Isotope Technology (BRIT), Mu mbai. Details regarding the isotopes used in the present experimental work are given in Table 2. Table 2. Properties of 131I and 82Br tracer isotopes[6] Isotopes 131I 82Br Half-life 8.04 days 36 hours Radio act iv ity / mCi 5 5 γenergy / MeV 0.36 0.55 Chemical form Iodide* Bromide** Physical form Aqueous Aqueous * Sodium iodide in dilute sodium sulphite. ** Ammonium bromide in dilute ammonium hydroxide In a stoppered bottle 250 mL (V) of 0.001 M iodide ion solution was labeled with diluted 131I radioactive solution using a micro syringe, such that 1.0 mL of labeled solution has a radioactivity of around 15,000 cp m (counts per minute) when measured with γ -ray spectrometer having NaI (Tl) scintillat ion detector. Since only about 50–100 μL of the radioactive iodide ion solution was required for labeling the solution, its concentration will remain unchanged, which was further confirmed by potentiometer t itration against AgNO3 solution. The above labeled solution of known initial activity (Ai) was kept in a thermostat adjusted to 30.0 °C. The swelled and conditioned dry ion exchange resins in iodide form weighing exact ly 1.000 g (m) were transferred qu ickly into this labeled solution which was vigorously stirred by using mechanical stirrer and the activity in cpm of 1.0 mL of solution was measured. The solution was transferred back to the same bottle containing labeled solution after measuring activity. The iodide ion-isotopic exchange reaction can be represented as: R-I + I*-(aq.) R-I* + I-(aq.) (1) Here R-I represents ion exchange resin in iodide form; I*-(aq.) represents aqueous iodide ion solution labeled with 131I radiotracer isotope. The activity of solution was measured at a fixed interval of every 2.0 min. The final act ivity (Af) of the solution was also measured after 3h wh ich was sufficient time to attain the equilibriu m[7-13]. The activity measured at various time intervals was corrected for background counts. Similar experiments were carried out by equilibrat ing separately 1.000 g of ion exchange resin in iodide form with labeled iodide ion solution of four different concentrations ranging up to 0.004 M at a constant temperature of 30.0℃. The same experimental sets were repeated for higher temperatures up to 45.0℃. 2.4. Study on Kinetics of Bromi de Ion-Isotopic Exchange Reac tion The experiment was also performed to study the kinetics of bromide ion- isotopic exchange reaction by equilibrating 1.000 g of ion exchange resin in bromide form with labeled bromide ion solution in the same concentration and temperature range as above. The labeling of bro mide ion solution was done by using 82Br as a radioactive tracer isotope for which the same procedure as explained above was followed. The bro mide ion-isotopic exchange reaction can be represented as: R-Br + Br*-(aq.) R-Br* + Br - (aq.) (2) Here R-Br represents ion exchange resin in bro mide form; Br*-(aq.) represents aqueous bromide ion solution labeled with 82Br radiotracer isotope. 3. Results and Discussion 2.3. Study on Kinetics of Iodi de Ion-Isotopic Exchange Reac tion 3.1. Comparati ve Study of Ion-Isotopic Exchange Reac tions International Journal of M aterials and Chemistry 2012, 2(4): 151-157 153 In the present investigation it was observed that due to the rapid ion-isotopic exchange reaction taking p lace, the activity of solution decreases rapidly initially, then due to the slow exchange the activity of the solution decreases slowly and finally remains nearly constant. Preliminary studies show that the above exchange reactions are of first order[14, 15]. 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[7-13]. Now the straight line was e xtrapolated back to ze ro time. The extrapolated portion represents the contribution of slow process to the total activity which now includes rapid p rocess also. The activity due to slow p rocess was subtracted from the total activity at various time intervals. The d ifference gives the activity due to rapid process only. From the activity exchanged due to rapid process at various time intervals, the specific react ion rates (k) of rap id ion-isotopic exchange reaction were calculated. The amount of iodide / bro mide ions exchanged (mmol) on the resin were obtained fro m the initial and final activ ity of solution and the amount of exchangeable ions in 250 mL of solution. Fro m the amount of ions exchanged on the resin (mmo l) and the specific reaction rates (min-1), the init ial rate of ion exchanged (mmo l/ min) was calcu lated. Because of larger solvated size of bro mide ions as compared to that of iodide ions, it was observed that the exchange of bro mide ions occurs at the slower rate than that of iodide ions[16]. Hence under identical experimental conditions, the values of specific react ion rate (min-1), amount of ion exchanged (mmo l) and in itial rate of ion exchange (mmo l/ min) are calculated to be lower for bro mide ion-isotopic exchange reaction than that for iodide ion-isotopic exchange reaction as summarized in Tables 3 and 4. For both bromide and iodide ion-isotopic exchange reactions, under identical experimental conditions, the values of specific react ion rate increases with increase in concentration of ionic solution from 0.001M to 0.004M (Table 3). Ho wever, with rise in temperature fro m 30.0℃ to 45.0℃, the specific reaction rate was observed to decrease (Table 4). Fro m the results, it appears that iodide ions exchange at the faster rate as co mpared to that of bro mide ions which was related to the extent of solvation (Tables 3 and 4). INDION 810 (I131) INDION -454(I131) INDION -810 (Br82) INDION-454 (Br82) Log of Activity 4.50 4.00 3.50 3.00 0 20 40 60 80 100 Time (min) Figure 1. Kinetics of Ion-Isotopic Exchange Reactions Amount of ion exchange resin = 1.000 g, Concentration of labeled exchangeable ionic solution = 0.001M, Volume of labeled ionic solution = 250 mL, Temperat ure = 30.0℃ Table 3. Concent rat ion effect on Ion-Isot opic Exchange React ions Amount of ion exchange resin = 1.000 g, Volume of labeled ionic solut ion = 250 mL, Temperat ure = 30.0℃ REACT ION -1 INDION-810 INDION -454 REACT ION -2 INDION-810 INDION -454 Concentration of ionic solution (M) Amount of ions in 200 mL solution (mmol) Specific reaction rate of rapid process min-1 Amount of iodide ion exchanged (mmol) Initial rate of iodide ion exchange (mmol/min) Log Kd Specific reaction rate of rapid process min-1 Amount of iodide ion exchanged (mmol) Initial rate of iodide ion exchanged (mmol/min) Log Kd Specific reaction rate of rapid process min-1 Amount of bromide ion exchanged (mmol) Initial rate of bromide ion exchange (mmol/min) Log Kd Specific reaction rate of rapid process min-1 Amount of bromide ion exchanged (mmol) Initial rate of bromide ion exchange (mmol/min) Log Kd 0.001 0.250 0.002 0.500 0.102 0.083 0.008 12.4 0.153 0.120 0.018 12.8 0.078 0.065 0.005 7.8 0.131 0.104 0.014 8.1 0.121 0.194 0.023 13.6 0.168 0.253 0.043 14.0 0.091 0.149 0.014 8.3 0.143 0.226 0.032 8.6 0.003 0.750 0.137 0.326 0.045 14.5 0.179 0.386 0.069 14.9 0.107 0.260 0.028 9.1 0.155 0.363 0.056 9.4 0.004 1.000 0.146 0.461 0.067 15.8 0.196 0.526 0.103 16.2 0.120 0.384 0.046 9.6 0.168 0.506 0.085 9.9 154 Pravin U. Singare: Comparative Study of Indion-810 and Indion -454 Strongly Basic Anion Exchange Resins by Application of 131I and 82 Br as a Tracer Isotopes Table 4. Temperat ure effect on Ion-Isotopic Exchange React ions Amount of ion exchange resin = 1.000 g, Concentrat ion of labeled exchangeable ionic solut ion = 0.001M, Volume of labeled ionic solut ion = 250 mL, Amount of exchangeable ions in 250 mL labeled solut ion = 0.250mmol REACT ION -1 INDION-810 INDION -454 REACT ION -2 INDION-810 INDION -454 Temperature 0 C Specific reaction rate of rapid Process min-1 Amount of iodide ion exchanged (mmol) Initial rate of iodide ion exchange (mmol/min) Log Kd Specific reaction rate of rapid Process min-1 Amount of iodide ion exchanged (mmol) Initial rate of iodide ion exchange (mmol/min) Log Kd Specific reaction rate of rapid Process min-1 Amount of bromide ion exchanged (mmol) Initial rate of bromide ion exchange (mmol/min) Log Kd Specific reaction rate of rapid Process min-1 Amount of bromide ion exchanged (mmol) Initial rate of bromide ion exchange (mmol/min) Log Kd 30.0 0.102 0.083 0.008 12.4 0.153 0.120 0.018 12.8 0.078 0.065 0.005 7.8 0.131 0.104 0.014 8.1 35.0 0.090 0.074 0.007 11.9 0.145 0.115 0.017 12.3 0.072 0.060 0.004 7.1 0.125 0.100 0.012 7.4 40.0 0.082 0.068 0.006 11.5 0.139 0.110 0.015 11.9 0.068 0.057 0.004 6.7 0.119 0.095 0.011 7.0 45.0 0.075 0.062 0.005 10.9 0.132 0.105 0.014 11.3 0.065 0.055 0.004 6.2 0.115 0.092 0.011 6.5 INDION-810 (Reaction 1) INDION-810 (Reaction 2) 60 INDION -454 (Reaction 1) INDION -454 (Reaction 2) 46.1 52.58 38.4 50.6 43.41 51.45 34.6 48.46 38.7 50.6 29.7 45.2 48.18 41.67 33 25.8 Percentage of ions exchanged 40 20 0.004 0.003 0.002 0.001 0 Concentration of labeled ionic solution (M) Figure 2. Variation in Percentage Ions Exchanged with Concentration of Labeled Ionic Solution Amount of ion exchange resin = 1.000 g, Volume of labeled ionic solut ion = 250 mL, Temperat ure = 30.0℃ International Journal of M aterials and Chemistry 2012, 2(4): 151-157 155 INDION-810 (Reaction 1) INDION-810 (Reaction 2) 80 INDION -454 (Reaction 1) INDION-454 (Reaction 2) 41.96 43.99 36.9 38.1 29.4 45.8 24 39.9 48.18 41.67 Percentage ions exchanged 60 33 40 21.9 24.9 22.8 27 25.8 20 0 45.0 40.0 35.0 30.0 Temperature (0 C) Figure 3. Variation in Percentage Ions Exchanged with T emperature of Labeled Ionic Solution Amount of ion exchange resin = 1.000 g, Concentration of labeled exchangeable ionic solution = 0.001M, Volume of labeled ionic solution = 250 mL, Amount of exchangeable ions in 250 mL labeled solution = 0.250 mmol Fro m the knowledge of Ai, Af, volume of the exchangeable ionic solution (V) and mass of ion exchange resin (m), the Kd value was calculated by the equation Kd =[(Ai - Af) / A f] x V / m (3) Heu mann et al.[17] in the study of chloride distribution coefficient on strongly basic anion exchange resin observed that the selectivity coefficient between halide ions increased at higher electro lyte concentrations. Adachi et al.[18] observed that the swelling pressure of the resin decreased at higher solute concentrations resulting in larger Kd values. The temperature dependence of Kd values on cation exchange resin was studied by Shuji et al.[19]; were they observed that the values of Kd increased with fall in temperature. The present experimental results also indicates that the Kd values for bromide and iodide ions increases with increase in ionic concentration of the external solution, however with rise in temperature the Kd values were found to decrease. It was also observed that the Kd values for iodide ion-isotopic reaction were calculated to be higher than that for bro mide ion-isotopic reaction (Tables 3 and 4). 3.2. Comparati ve Study of Anion Exchange Resins Fro m the Table 3, it is observed that for iodide ion-isotopic exchange reaction by using Indion-454 resin, the values of specific reaction rate (min-1), amount of iodide ion exchanged (mmo l), init ial rate of iodide ion exchange (mmo l/ min) and log Kd were 0.153, 0.120, 0.018 and 12.8 respectively, which was higher than 0.102, 0.083, 0.008 and 12.4 respectively as that obtained by using Indion-810 resins under identical experimental conditions of 30.0℃, 1.000 g of ion exchange resins and 0.001 M labeled iodide ion solution. The identical trend was observed for the two resins during bromide ion-isotopic exchange reaction. Figure 4. Correlation between concentrations of iodide ion solution and amount of iodide ion exchanged Amount of ion exchange resin = 1.000 g, Volume of labeled ionic solution = 250 mL, Temperature = 30.0℃ Correlation coefficient (r) for Indion-454 = 0.9999 Correlation coefficient (r) for Indion-810 = 0.9990 Fro m Table 3, it is observed that using Indion-454 resins, at a constant temperature of 30.0℃, as the concentration of labeled iodide ion solution increases 0.001 M to 0.004 M, the percentage of ions exchanged increases from 48.18 % to 52.58 %. While using Indion-810 resins under identical experimental conditions the percentage of ions exchanged increases fro m 33.00 % to 46.10 %. Similarly in case of bromide ion-isotopic exchange reaction, the percentage of ions exchanged increases from 41.67 % to 50.60 % using Indion-454 resin, while for Indion-810 resin it increases 156 Pravin U. Singare: Comparative Study of Indion-810 and Indion -454 Strongly Basic Anion Exchange Resins by Application of 131I and 82 Br as a Tracer Isotopes fro m 25.80 % to 38.40 %. The effect of ionic concentration on percentage of ions exchanged is graphically represented in Figure 2. Indion-454 resin, while for Indion-810 resin it decreases fro m 25.80 % to 21.90 %. The effect of temperature on percentage of ions exchanged is graphically represented in Figure 3. The overall results indicate that under identical experimental conditions, as compared to Indion-810 resins, Indion-454 resins shows higher percentage of ions exchanged. Thus Indion-454 resins show superior performance than Indion-810 resins. Figure 5. Correlation between concentrations of bromide ion solution and amount of bromide ion exchanged Amount of ion exchange resin = 1.000 g, Volume of labeled ionic solution = 250 mL, T emperature = 30.0℃ Correlation coefficient (r) for Indion-454 = 0.9994 Correlation coefficient (r) for Indion-810 = 0.9964 Figure 6. Correlation between T emperature of exchanging medium and amount of iodide ion exchanged .Amount of ion exchange resin = 1.000 g, Concentration of labeled exchangeable ionic solution = 0.001M, Volume of labeled ionic solution = 250 mL, Amount of exchangeable ions in 250 mL labeled solution = 0.250 mmol Correlation coefficient (r) for Indion-454 = -1.0000 Correlat ion coefficient (r) for Indion-810 = -0.9944 Fro m Table 4, it is observed that using Indion-454 resins, for 0.001 M labeled iodide ion solution, as the temperature increases 30.0 ℃ to 45.0 ℃ , the percentage of ions exchanged decreases from 48.18 % to 41.96 %. While using Indion-810 resins under identical experimental conditions the percentage of iodide ions exchanged decreases from 33.00 % to 24.90 %. Similarly in case of bro mide ion-isotopic exchange reaction, the percentage of ions exchanged decreases fro m 41.67 % to 36.90 % using Figure 7. Correlation between Temperatures of exchanging medium and amount of bromide ion exchanged .Amount of ion exchange resin = 1.000 g, Concent ration of labeled exchangeable ionic solut ion = 0.001M, Volume of labeled ionic solution = 250 mL, Amount of exchangeable ions in 250 mL labeled solution = 0.250 mmolCorrelation coefficient (r) for Indion-454 = -0.9959 Correlat ion coefficient (r) for Indion-810 = -0.9795 3.3. Statistical Correlations The results of present investigation show a strong positive linear co-relationship between amount of ions exchanged and concentration of ionic solution (Figures 4, 5). In case of iodide ion exchange using Indion-454 and Indion-810 resins, the values of correlation coefficient (r) were found to be 0.9999 and 0.9990, while for b ro mide ion exchange the values of r were 0.9994 and 0.9964 respectively. There also exist a strong negative co-relationship between amount of ions exchanged and temperature of exchanging mediu m (Figures 6, 7). For Indion-454 and Indion-810 resins, during iodide ion-isotopic exchange the values of r were found to be -1.0000 and -0.9944 respectively; while fo r bro mide ion-isotopic exchange the values were calcu lated as -0.9959 and -0.9795 respectively for the two resins. 4. Conclusions The experimental work carried out in the present investigation will help to standardize the operational process parameters so as to improve the performance of selected nuclear grade ion exchange resins. The radioactive tracer International Journal of M aterials and Chemistry 2012, 2(4): 151-157 157 technique used here can also be applied for characterization of different nuclear as well as non-nuclear grade ion exchange resins. ACKNOWLEDGEMENTS The author is thankful to Professor Dr. R.S. Lokhande for his valuable help and support in carrying out the experimental work in Rad iochemistry Laboratory of Depart ment of Chemistry, University of Mu mbai, Vidyanagari, Mu mbai -58. The authors are extremely thankful to SAP Productions for developing and maintaining the manuscript temp late. REFERENCES [1] International Atomic Energy Agency, 1967, Operation and Control of Ion exchange Processes for Treatment of Radioactive Wastes, Technical Report Series No. 78, IAEA, Vienn a. [2] International Atomic Energy Agency, 1984, Treatment of Low and Intermediate-level Liquid Radioactive Wastes, Technical Report Series No. 236, IAEA, Vienna. [3] International Atomic Energy Agency, 2002, Application of Ion exchange processes for the treatment of Radioactive Waste and M anagement of Spent Ion Exchangers, Technical Report Series No.408, IAEA, Vienna. [4] Sood, D.D., Reddy, A.V.R., and Ramamoorthy, N., 2004, ‘Applications of Radioisotopes in Physico-Chemical Investigations’, in Fundamentals of Radiochemistry, Indian Association of Nuclear Chemists and Allied Scientists (IANCAS), 253-263. [5] International Atomic Energy Agency, 2004, Radiotracer Applications in Industry- A Guidebook, Safety Reports Series No. 423, IAEA, Vienna. [6] Sood, D.D., 1998, Proc. Int. Conf. on Applications of Radioisotopes and Radiation in Industrial Development, ed. Sood, D.D., Reddy, A.V.R., Iyer, S.R.K., Gangadharan, S., and Singh, G., (B.A.R.C., India), 35–53. [7] Singare, P.U., and Lokhande, R.S., 2012, Studies on Ion-Isotopic Exchange Reactions Using Nuclear Grade Ion Exchange Resins., Ionics, 18(4), 351–357. [8] Singare, P.U., Lokhande, R.S., and Patil, A.B., 2008, Application of Radioactive Tracer Technique for Characterization of some Strongly Basic Anion Exchange Resins., Radiochim. Acta, 96(2), 99-104. [9] Lokhande, R.S., and Singare, P.U., 2008, Comparative Study on Iodide and Bromide Ion-Isotopic Exchange Reactions by Application of Radioactive Tracer Technique., J.Porous M ater, 15(3), 253-258. [10] Singare, P.U., Lokhande, R.S., and Patil, A.B., 2007, Application of Radioactive Tracer Technique on Industrial Grade Ion Exchange Resins Indion-830 (Type-1) and Indion-N-IP (Type-2)., Radiochim. Acta, 95(1), 111-114. [11] Lokhande, R.S., and Singare, P.U., 2007, Comparative Study on Ion-Isotopic Exchange Reaction Kinetics by Application of Tracer Technique., Radiochim. Acta, 95(3), 173-176. [12] Lokhande, R.S., Singare, P.U., and Kolte, A.R., 2007, Study on Kinetics and M echanism of Ion-Isotopic Exchange Reaction Using Strongly Basic Anion Exchange Resins Duolite A- 101 D and Duolite A-102 D., Radiochim. Acta, 95(10), 595-600. [13] Lokhande, R.S., Singare, P.U., and Dole, M .H., 2006, Comparative Study on Bromide and Iodide Ion-Isotopic Exchange Reactions Using Strongly Basic Anion Exchange Resin Duolite A-113., J.Nuclear and Radiochemical Sciences, 7(2), 29-32. [14] Lokhande, R.S., and Singare, P.U., 2003, Study of reversible ion-isotopic self diffusion reaction using 82 Br as a radioactive tracer isotope., Asian J. Chem., 15(1), 33-37. [15] Lokhande, R.S., and Singar e, P.U., 2005, Study on kinetics of self diffusion reaction by application of 82 Br as a radioactive tracer isotope., Asian J. Chem., 17(1), 125-128. [16] Shannon, R.D., 1976, Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides., Acta Crystallographica, A32, 751-767. [17] Heumann, K.G., and Baier, K., 1982, Chloride distribution coefficient on strongly basic anion-exchange resin: Dependence on co-ion in alkali fluoride solutions., Chromatographia, 15(11), 701-703. [18] Adachi, S., M izuno, T., and M atsuno, R., 1995, Concentration dependence of the distribution coefficient of maltooligosaccharides on a cation-exchange resin., J. Chromatography A, 708(2), 177-183. [19] Shuji, A., Takcshi, M ., and Ryuichi, M ., 1996, Temperature dependence of the distribution coefficient of maltooligosaccharides on cation-exchange resin in Na+ form., Bioscience, Biotechnology, and Biochemistry, 60(2), 338-340.

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