PL
 |
EN
Preferencje help
Polish version English version Język
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 8

Liczba wyników na stronie
first rewind previous Strona / 1 next fast forward last
Wyniki wyszukiwania
Wyszukiwano:
w słowach kluczowych:  anion exchange resins
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 1 next fast forward last
1
Content available Study on Halide Ions Selectivity of Nuclear Grade Anion Exchange Resin Auchlite ARA-9366
Singare P. U., Patange A. N.
International Letters of Chemistry, Physics and Astronomy
|
2014
|
Vol. 11, iss. 1
67-73
EN
The selectivity behaviour of nuclear grade anion exchange resin Auchlite ARA-9366 in chloride form towards iodide and bromide ions in the solution was studied. The trend in selectivity of the resin was predicted on the basis of thermodynamics of Clˉ/Iˉ and Clˉ/Brˉ uni-univalent ion exchange reactions. It was observed that the equilibrium constants K values for Clˉ/Iˉ ion exchange reaction were higher than that calculated for Clˉ/Brˉ exchange under identical experimental conditions. Also the enthalpy values for the two uni-univalent ion exchange reactions were calculated as -47.87 and -36.14 kJ/mol respectively. The high K and low enthalpy values obtained for Clˉ/Iˉ ion exchange reaction as compared to that obtained during Clˉ/Brˉ exchange supports higher selectivity of the resin towards iodide ions as compared to that towards bromide ions, when both the ions are present in the same solution.
2
Content available Study on Halide Ions Selectivity of Industrial Grade Anion Exchange Resin Auchlite A-378
Singare P. U., Patange A. N.
International Letters of Chemistry, Physics and Astronomy
|
2014
|
Vol. 11, iss. 1
44-50
EN
The thermodynamic approach was applied to predict the trend selectivity of industrial grade anion exchange resin Auchlite A-378 in chloride form towards iodide and bromide ions in the solution. The study was conducted by performing the Clˉ/Iˉ and Clˉ/Brˉ uni-univalent ion exchange reactions under gradually increasing temperature conditions. The thermodynamic equilibrium constants K values were used to calculate the enthalpies of the two uni-univalent ion exchange reactions. It was observed that the K values for Clˉ/Iˉ ion exchange reaction were higher than Clˉ/Brˉ exchange reaction under identical experimental conditions. Also the enthalpy values for the two uni-univalent ion exchange reactions were calculated as -39.51 and -18.38 kJ/mol respectively. The high K and low enthalpy values obtained for Clˉ/Iˉ ion exchange reaction is responsible for higher selectivity of the resin towards iodide ions as compared to that towards bromide ions, when both the ions are present in the same solution.
3
Content available Radiotracer Technique in Study of Strongly Basic Anion Exchange Resins Dowex-SBR LC and Indion-454
Singare P. U.
International Letters of Chemistry, Physics and Astronomy
|
2013
|
Vol. 13
37-49
EN
The present paper demonstrates application of isotopic tracer technique in characterization of anion exchange resins Dowex-SBR LC and Indion-454 for which 131I and 82Br radio isotopes were used. The characterization was made based on iodide and bromide ion-isotopic exchange reaction kinetic data obtained for the two resins. It was observed that during iodide ion-isotopic exchange reaction performed at 35.0 °C, 1.000 g of ion exchange resins and 0.002 mol/L labeled iodide ion solution, the values of specific reaction rate (min-1), amount of ion exchanged (mmol), initial rate of ion exchange (mmol/min) and log Kd were 0.379, 0.426, 0.161 and 16.2 respectively for Dowex-SBR LC resin, which was higher than the respective values of 0.156, 0.243, 0.038 and 13.4 as that obtained by using Indion-454 resins. The identical trend was observed for the two resins during bromide ion-isotopic exchange reaction. The results of present investigation also indicate that during the two ion-isotopic exchange reactions, for both the resins, there exists a strong positive linear correlation between amount of ions exchanged and concentration of ionic solution; and strong negative correlation between amount of ions exchanged and temperature of exchanging medium. Based on overall results it appears that under identical experimental conditions, as compared to Indion-454 resins, Dowex-SBR LC resins show superior performance. 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.
4
Content available Radioisotopic tracer technique for characterization of nuclear and non-nuclear grade ion exchange resins Tulsion A-23 and Indion-810
Singare P. U.
International Letters of Chemistry, Physics and Astronomy
|
2013
|
Vol. 6
1-5
EN
In the present paper 82Br radioactive tracer isotopes was used for characterization of nuclear and non-nuclear grade ion exchange resins Tulsion A-23 and Indion-810 respectively. The bromide ion-isotopic exchange reactions were performed by equilibrating 1.000 g of conditioned resins in bromide form with labeled bromide ion solution of different concentrations ranging from 0.001 M to 0.004 M, in the temperature range of 30.0 °C to 45.0 °C. The resins were characterized by comparing the values of specific reaction rate (min-1), amount of bromide ion exchanged (mmol) and percentage of bromide ions exchanged under identical experimental conditions. It was observed that the above values decrease with rise in temperature and increases with increase in concentration of labeled bromide ion solution. From the experimental values of specific reaction rate, amount and percentage of bromide ions exchanged, it was observed that Tulsion A-23 resins are superior to Indion-810 resins under identical experimental conditions.
5
Content available Non Destructive Application of Radioactive Tracer Isotopes for Performance Evaluation of Industrial Grade Anion Exchange Resins Tulsion A-33 and Indion NSSR
Singare P. U.
International Letters of Chemistry, Physics and Astronomy
|
2013
|
Vol. 13
50-62
EN
The present study deals with non-destructive application of radioactive tracer isotopes to evaluate the performance of Tulsion A-33 (nuclear grade) and Indion NSSR (non-nuclear grade) anion exchange resins. The performance evaluation was done by carrying out the iodide and bromide ion-isotopic exchange reactions using the above resins. It was observed that at a constant temperature of 40.0 °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 58.0 % to 64.0 % for Tulsion A-33 resins; and from 48.4 % to 50.8 % for Indion NSSR resins. Similarly in case of bromide ion-isotopic exchange reaction under identical experimental conditions, the percentage of bromide ions exchanged increases from 45.6 % to 50.4 % for Tulsion A-33 resin; and from 39.8 % to 44.6 % for Indion NSSR resin. It was also observed that during iodide ion-isotopic exchange reaction at 40.0 °C, using 1.000 g of ion exchange resins and 0.003 M labeled ionic solution, using Tulsion A-33 resin the values of specific reaction rate (min-1), amount of iodide ion exchanged (mmol), initial rate of iodide ion exchange (mmol/min) and log Kd were 0.229, 0.469, 0.107 and 10.6 respectively, which was higher than the values of 0.167, 0.375, 0.063 and 7.6 respectively as obtained by using Indion NSSR resins under identical experimental conditions. The overall results indicate superior performance of Tulsion A-33 over Indion NSSR resin under identical operational parameters.
6
Content available remote Separation of anionic surface-active agents in an integrated ion exchange-sedimentation-ultrafiltration purification system
Kowalska I.
Environment Protection Engineering
|
2010
|
Vol. 36, nr 3
33-42
EN
The efficiencies of separation of anionic surface-active agents (ASAAs) from aqueous solutions below the critical micelle concentration were determined in an integrated purification system combining ion exchange, sedimentation and ultrafiltration. The tests were carried out using five types of anion-exchange resins (strongly and weakly basic) and flat polyethersulfone membranes with cut-off values of 5, 10 and 30 kDa. Combination of ion exchange and low-pressure membrane separation processes was found to facilitate effective separation of ASAAs from aqueous solutions below the critical micelle concentration. Integration of both unit processes was observed to be most beneficial in the case of membrane with the highest cut-off (30 kDa), which was characterized by low ASAA retention factors when ultrafiltration was carried out as a standalone process. The presence of the ion-exchange resin was also found to allow a significant reduction in membrane fouling and retention of high hydraulic efficiency.
7
Content available remote Removal of nitrates from water by selective ion exchange
Dziubek A. M., Maćkiewicz J.
Environment Protection Engineering
|
2009
|
Vol. 35, nr 1
171-177
EN
The applicability of ion exchange on selective anion-exchange resins to the removal of nitrates from groundwater which was to serve for drinking purposes was investigated. The concentration of nitrates in the groundwater treated in the ion-exchange process, in the presence of chloride ions (50 g Cl(-)/m3) and sulfate ions (90 g SO4(-2) /m3), varied from 15 to 30 g N/m3. The velocity of water flow through the ion-exchange column ranged between 10 and 25 m/h. The exchange capacity of the resin with respect to nitrates determined in the experimental study was 0.5 val/dm3. The efficiency of the ion-exchange process up to the exhaustion of the ion-exchange capacity of the resin (expressed as the ratio of the treated water volume to the resin volume) was found to vary from 200 to 400.
PL
Omówiono wyniki badań nad możliwością usuwania azotanów z wód podziemnych przeznaczonych do spożycia. W badaniach określono przydatność procesu wymiany jonowej na selektywnych żywicach anionowymiennych do usuwania azotanów z wody. Uwzględniono wpływ chlorków (50 g Cl(-)/m3) i siarczanów (90 g SO4(-2) /m3) oraz prędkości procesu (10-25 m/h) na jego skuteczność. Wyznaczono zdolność wymienną żywicy w stosunku do azotanów na poziomie 0,5 val/dm3. Ustalono także, że wydajność procesu wymiany jonowej do momentu wyczerpania zdolności jonowymiennej żywicy, wyrażona jako stosunek objętości oczyszczonej wody do objętości żywicy, wynosiła 200-280.
8
Content available remote Zastosowanie czynników kompleksujących w procesie usuwania kadmu(ll) z roztworów wodnych
Kołodyńska D., Hubicki Z.
Przemysł Chemiczny
|
2008
|
T. 87, nr 7
781-785
first rewind previous Strona / 1 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.