Ion-Isotopic exchange reaction kinetics in characterization of anion exchange resins Dowex 550A LC and Indion-820

The present paper involves application of nondestructive radioactive tracer technique in characterization of Dowex 550A LC and Indion-820 anion exchange resins. The characterization study was based on kinetic of exchange reactions between inactive iodide/bromide ions on the resins with radioactive iodide/bromide ions in the solution. During iodide exchange reaction performed at a constant temperature of 40.00C, using 1.000 g of ion exchange resins and labeled iodide ion solution of concentration 0.003 mol/L, for Dowex 550A LC resin the specific reaction rate and initial rate of ion exchange was 0.271 min-1 and 0.141 mmol/min respectively, while the amount of iodide ions exchanged was 0.522 mmol, and log Kd was calculated to be 12.1. The above values calculated for Dowex 550A LC resin was higher than the respective values of 0.108, 0.330, 0.036 and 6.0 as obtained for Indion-820 resins. Similar results were obtained for the two resins during bromide exchange reactions, thereby indicating superior performance of Dowex 550A LC resin over Indion-820 resins

Ion exchange equilibrium for some uni-univalent and uni-divalent reaction systems using strongly basic anion exchange resin Duolite A-102 D

The study on thermodynamics of ion exchange equilibrium for uni-univalent Cl-/I-, Cl-/Br-, and uni-divalent Cl-/SO42-, Cl-/C2O42- reaction systems was carried out using ion exchange resin Duolite A-102 D. The equilibrium constant K was calculated by taking into account the activity coefficient of ions both in solution as well as in the resin phase. The K values calculated for uni-univalent and uni-divalent anion exchange reaction systems was observed to increase with rise in temperature, indicating the endothermic exchange reactions having enthalpy values of 13.7, 38.0, 23.9, 22.9 kJ/mol, respectively. KEY WORDS: Duolite A-102 D ion exchange resin, Equilibrium constant, Endothermic ion exchange reaction, Enthalpy, Thermodynamic study  Bull. Chem. Soc. Ethiop. 2008, 22(1), 107-114

Characterization Study of Anion Exchange Resins Tulsion A-33 and Indion H-IP by Application of 131 I and 82 Br as a Tracer Isotopes Using γ-Ray Spectrometer

Abstract The present paper deals with the application of 131 I and 82 Br radioactive tracer isotopes in characterizat ion of strong base, nuclear grade anion exchange resin Tulsion A-33 and intermed iate base, non-nuclear grade anion exchange resin Indion H-IP. The characterizat ion study was performed by using γ-ray spectrometer having Na(I) Tl scintillat ion detector. The two radioactive tracer isotopes were used to trace iodide and bro mide ion-isotopic exchange react ions taking place between the ion exchange resins and external ionic solution of different concentrations varying fro m 0.001M to 0.004 M, in the temperature range of 30.0 0C to 45.0 0C. The characterization o f the t wo resins was made by co mparing the values of specific reaction rat e (min-1), percentage of ions exchanged, and distribution coefficient (Kd) values. It was observed that under identical experimental conditions, above values were calculated higher for Tulsion A-33 as co mpared to Indion H-IP resins, indicat ing superior performance of Tulsion A-33. It is expected that the radioactive tracer technique as applied in the present investigation will find important role not only in characterization of various ion exchange materials, but also in optimizat ion of variou s industrial process parameters so as to bring about the efficient performance of selected resin

Vrednovanje industrijskih smola Duolite ARA-9366 i Duolite A-368 na osnovi učinka

This study deals with performance evaluation of nuclear and non-nuclear grade resins Duolite ARA-9366 and Duolite A-368 by application of the radioanalytical technique. The evaluation was made based on kinetics data of ion-isotopic exchange reactions using 131I and 82Br radioactive tracer isotopes. It was observed that under identical experimental conditions of 35.0 °C, 1.000 g of ion exchange resins and 0.002 mol l -1 labelled iodide ion solution, the values of specific reaction rate in min-1 and initial rate of iodide ion exchange in mmol min -1 was 0.173 and 0.044 respectively for Duolite ARA-9366 resin; that was higher than the values of 0.129 and 0.030 respectively reported for Duolite A-368 resins. The identical trend was observed for the two resins during bromide ion-isotopic exchange reaction. The results of this investigation show the existence of a strong positive co-relationship between the amount of ions exchanged and the concentration of ionic solution; as well as the existence of a strong negative co-relationship between the amount of ions exchanged and the temperature of the exchanging medium for both resins. The overall results indicate superior performance of Duolite ARA-9366 over Duolite A-368 under identical experimental conditions.Istraživane su smole nuklearne i nenuklearne kvalitete Duolit ARA-9366 i Duolit A-368 radioanalitičkim metodama. Vrednovanje je temeljeno na kinetici ionske izmjene radioaktivnih obilježivača 151I i 82Br. Pod istim eksperimentalnim uvjetima (35,0 °C; 1,000 g ionskoizmjenjivačke smole; koncentracija jodida 0,002 mol l−1 u obilježenoj otopini) specifične brzine reakcije i početne brzine ionske izmjene bile su 0,173 min−1 i 0,044 mmol min−1 za Duolite ARA-9366, što je više nego 0,129 min−1 i 0,030 mmol min−1 za Duolite A-368. Jednaka tendencija uočena je u izotopnoj izmjeni bromidnog iona. Za obje smole utvrđena je jaka korelacija između množine izmijenjenih iona i koncentracije iona, te jaka negativna korelacija između množine izmijenjenih iona i temperature. Rezultati istraživanja pokazuju veću učinkovitost smole Duolite ARA-9366 od Duolite A-368 pri jednakim eksperimentalnim uvjetima

Study on distribution coefficient of bromide ions from aqueous solution on ion exchange resins Indion-850, Indion-860 and Indion FF-IP

The ion exchange resin Indion-850, Indion-860 and Indion FF-IP, in bromide form were equilibrated separately with the labeled radioactive bromide ion solution of different concentrations varying from 0.005 M to 0.100 M in the temperature range of 25.0 oC to 45.0 oC. The Kd values of bromide ions were observed to be high for Indion-850 and least for Indion 860, while Indion FF-IP shows intermediate Kd values under identical experimental conditions. The difference in Kd values of bromide ions for the three resins is mainly because of the swelling pressure which depends on their water holding capacities

Toxicity Study of Heavy Metals Pollutants in Waste Water Effluent Samples Collected From Taloja Industrial Estate of Mumbai, India,

Abstract The present research work deals with the assessment of pollution due to toxic heavy metals in the industrial waste water effluents collected from Taloja industrial belt of Mumbai. The study reveals that dyes, paints, pharmaceutical and textile industries are some of the major industries contributing to the heavy metal pollutants in the surrounding aquatic environment. It was observed that paint manufacturing industries are the major contributors of toxic Cr, Zn and Pb amounting to 35.2, 33.1, and 31.4 mg/L respectively. It was also observed that major contribution of Cu (33.3 mg/L) was from dyes manufacturing units, while maximum Fe concentration of 12.8 mg/L was found in effluent samples released from textile industries. The concentration of Cd and Ni was found maximum in effluent samples collected from pharmaceutical industries amounting to 35.8 and 33.6 mg/L respectively. The overall results point out high concentration of toxic heavy metals in the effluent samples collected from different industries. These industrial effluents will pollute the near by water bodies affecting the growth of vegetation and aquatic life. These toxic heavy metals when released in aquatic environment will enter the food chain through bio-magnification causing various health problems in humans. The results of the present investigation point out the need to implement common objectives, compatible policies and programmes for improvement in the industrial waste water treatment methods

Sediment Contamination Due to Toxic Heavy Metals in Mithi River of Mumbai

Abstract The present study deals with quantification of accumulated toxic heavy metals in sediments of Mithi River of Mumbai. The study was performed at three different sampling locations along the flow of Mithi River for two years from 2009-12. The different heavy metals studied were Al, As, Cd, Cr, Hg, Ni, Pb, Sr and Mn. The results of our study indicate that the concentration level of these toxic heavy metals for the two assessment years increases by the factor of 1.2-5.8 µg/g. The result is a clear indication of day by day increasing pollution level of the Mithi River, which is creating negative environmental impact on biological life of the river. The results emphasises the need of regular scientific monitoring of different pollutants adversely affecting the environment and to reframe the pollution control strategies already in existence

THERMODYNAMICS OF UNI-UNIVALENT ION EXCHANGE REACTIONS USING STRONGLY ACIDIC CATION EXCHANGE RESIN TULSION T-46

Abstract The study on thermodynamics of ion exchange equilibrium for uni-univalent H + / Na + and H + / K + reaction systems was carried out using strongly acidic cation exchange resin Tulsion T-46. The equilibrium constant K calculated for uni-univalent ion exchange reaction systems were observed to increase with rise in temperature indicating the endothermic ion exchange reactions having the enthalpy values 4.19 and 3.80 kJ /mol respectively

Modelling of aortic aneurysm and aortic dissection through 3D printing

Introduction: The aim of this study was to assess if the complex anatomy of aortic aneurysm and aortic dissection can be accurately reproduced from a contrast-enhanced computed tomography (CT) scan into a three-dimensional (3D) printed model. Methods: Contrast-enhanced cardiac CT scans from two patients were post-processed and produced as 3D printed thoracic aorta models of aortic aneurysm and aortic dissection. The transverse diameter was measured at five anatomical landmarks for both models, compared across three stages: the original contrast-enhanced CT images, the stereolithography (STL) format computerised model prepared for 3D printing and the contrast-enhanced CT of the 3D printed model. For the model with aortic dissection, measurements of the true and false lumen were taken and compared at two points on the descending aorta. Results: Three-dimensional printed models were generated with strong and flexible plastic material with successful replication of anatomical details of aortic structures and pathologies. The mean difference in transverse vessel diameter between the contrast-enhanced CT images before and after 3D printing was 1.0 and 1.2 mm, for the first and second models respectively (standard deviation: 1.0 mm and 0.9 mm). Additionally, for the second model, the mean luminal diameter difference between the 3D printed model and CT images was 0.5 mm. Conclusion: Encouraging results were achieved with regards to reproducing 3D models depicting aortic aneurysm and aortic dissection. Variances in vessel diameter measurement outside a standard deviation of 1 mm tolerance indicate further work is required into the assessment and accuracy of 3D model reproduction. © 2017 Australian Society of Medical Imaging and Radiation Therapy and New Zealand Institute of Medical Radiation Technology

Remediation of radioiodine using polyamine anion exchange resins

Two weak base anion exchange resins, Lewatit A365 and Purolite MTS9850, have been tested for the removal of aqueous iodide from conditions simulating nuclear waste reprocessing streams. pH variation and relevant co-contaminant addition (nitrate, molybdate and iodine) allowed for assessment of iodide extraction behaviour of each resin. Isotherm experiments were performed and maximum uptake capacities obtained exceed current industrial adsorbents, such as silver-impregnated zeolites. Maximum loading capacities, determined by Dubinin–Radushkevich isotherm, were 761 ± 14 mg g−1 for MTS9850 and 589 ± 15 mg g−1 for A365. Uptake for both resins was significantly suppressed by nitrate and molybdate ions. The presence of dissolved iodine in the raffinate however, was found to increase iodide uptake. This was explained by characterisation of the spent resin surface by infrared and Raman spectroscopy, which determined the presence of triiodide, indicating charge-transfer complex formation on the surface. Dynamic studies assessed the effect of co-contaminants on iodide uptake in a column environment. Data was fitted to three dynamic models, with the Dose-Response model providing the best description of breakthrough. In all cases iodide breakthrough was accelerated, indicating suppression of uptake, but capacity was still significant