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EN
Radio analytical technique as a non-destructive technique was used in the present investigation to trace the kinetics of ion-isotopic exchange reaction taking place in Duolite ARA-9366 (nuclear grade) and Duolite A-171 (non-nuclear grade) anion exchange resins. The kinetics data suggest that during iodide ion-isotopic exchange reactions under identical experimental conditions of 40.00C, 1.000 g of ion exchange resins and 0.003 M 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 Kd were 0.176, 0.383, 0.067 and 7.8 respectively for Duolite ARA-9366 resin, which was higher than 0.142, 0.353, 0.050 and 7.0 respectively as that obtained for Duolite A-171 resins. Also it is 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 49.20 % to 51.80 % for Duolite ARA-9366 resins; and from 45.20 % to 47.80 % for Duolite A-171 resins. The similar trend was observed for the two resins during bromide ion-isotopic exchange reactions. The overall results indicate superior performance of Duolite ARA-9366 resins over Duolite A-171 resins under identical operational parameters.
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.
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.
EN
Isotopic tracer technique using 131I and 82Br was used to characterize Purolite NRW-6000 and Duolite A-143 anion exchange resins. The characterization study was done by carrying out iodide and bromide ion-isotopic exchange reactions taking place between the resin surface and the external labeled ionic solution. For the two resins it was observed that under identical experimental conditions, the values of specific reaction rate (min-1), amount of ion exchanged (mmol) and initial rate of ion exchange (mmol/min) were calculated to be lower for bromide ion-isotopic exchange reaction than that for iodide ion-isotopic exchange reaction. Also during both the ion-isotopic exchange reactions, under identical experimental conditions for the two resins, the values of specific reaction rate increases with increase in ionic concentration and was observed to decrease with rise in temperature. For a constant temperature of 35.0 °C, as the concentration of labeled bromide ion solution increases from 0.001 mol/L to 0.004 mol/L, the percentage of bromide ions exchanged increases from 67.80 % to 72.76 % using Purolite NRW-6000 resin and from 42.54 % to 50.45 % using Duolite A-143 resin. However when the temperature was raised from 30.0 °C to 45.0 °C by keeping the concentration of labeled bromide ion solution constant at 0.002 mol/L, the percentage of bromide ions exchanged decreases from 70.68 % to 67.32 % using Purolite NRW-6000 resin and from 47.50 % to 42.25 % using Duolite A-143 resin. From the results it appears that Purolite NRW-6000 resins show superior performance over Duolite A-143 resins under identical experimental conditions. It is expected that the present isotopic tracer technique can be applied further as an efficient nondestructive technique in characterization of various ion exchange resins so as to bring about their efficient industrial applications.
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.
EN
Ulhas River which is one of the most polluted rivers of Mumbai receives heavy pollution load from the nearby Dombivali industrial belt. Previous studies reported along the Dombivali industrial belt has indicated that the pollution level is so much alarming that it has created threat to nearby residential areas and also to the Ulhas River flowing in the outskirts of the Dombivali City. It is feared that the toxic chemicals present in the industrial waste might affect the sediment ecosystem of the river. Hence this has provoked us to carry the systematic and detailed study of physico chemical properties of the sediment samples collected along the Ulhas River. The study was done during the year 2012 and 2013, at the sites where the industrial discharge from Dombivli industrial belt Phase I and Phase II joins the Ulhas River. The study was performed to understand the physico chemical properties such as pH, alkalinity, chloride and phosphates. Results of the study reveal that there is an urgent requirement for systematic and regular monitoring of pollution level along the Ulhas River which will further help in improving the industrial waste treatment procedure adopted, along the Dombivli industrial belt. It is expected that such scientific studies will be useful to determine the extent of pollution control measures required in order to avoid long term irreparable damage to the Ulhas River ecosystem.
EN
The paper deals with monitoring of pollution arising due to agrochemicals and pesticides manufacturing industries located along the Dombivali industrial belt of Mumbai, India. The study was carried for the period of one year from June, 2012 to May, 2013 to study the level of toxic heavy metals and the physico-chemical properties of waste water effluents discharged from the above industries. The average concentration of Cu, Ni, Cr, Pb and Zn was found to be maximum of 29.86, 0.90, 1.16 and 1.19 ppm respectively in summer season, while average Fe concentration was maximum of 51.10 ppm in winter season. The average pH value of the effluent was found to be maximum of 12.95 in summer season, while average conductivity value was maximum of 21085 μmhos/cm in rainy season. The majority of physco-chemical parameters like alkalinity, hardness, salinity, chloride, cyanide, phosphate, total solid, BOD and COD content were found to be maximum in summer season having the average values of 1918, 186, 4, 11.20, 0.07, 81, 6391, 685 and 2556 ppm respectively. The average DO content was found to be low of 4.5 ppm in winter season. It was observed that the concentration level of majority of the toxic heavy metals and physico-chemical properties were above the tolerable limit set for inland surface water. The results of present study indicates that the existing situation if mishandled can cause irreparable ecological harm in the long term well masked by short term economic prosperity due to extensive industrial growth.
EN
The paper deals with monitoring of pollution arising due to fine chemicals manufacturing industries located along the Dombivali industrial belt of Mumbai, India. The study was carried for the period of one year from June, 2012 to May, 2013 to study the level of toxic heavy metals and the physico-chemical properties of waste water effluents discharged from the above industries. The concentration levels of heavy metals like Cu, Ni, Cr, Pb, Fe and Zn was found to be maximum of 45.94, 1.05, 7.50, 4.76, 145.87 and 21.96 ppm respectively in the effluents released during the months of February to April. The majority of physco-chemical parameters like alkalinity, salinity and chloride content were found to be maximum in the month of October having the concentration values of 1482, 4.91, 2710 ppm respectively, while the DO content in the effluents released in the same month was reported to be very much low having the value of 2.90 ppm. The effluents released during the month of June were reported to have high hardness, total solid (TS) content and COD values of 3713, 13638 and 6951 ppm respectively. The cyanide content (0.08 ppm), phosphate content (131.32 ppm) and BOD content (631 ppm) were found to be maximum in the months of December, February and May respectively. From the results it appears that as India moves towards stricter regulation of industrial effluents to control water pollution, greater efforts are required to reduce the risk to public health as toxic pollutants which are mainly colourless and odourless can be expected to be released into the ecosystems.
EN
The present study was performed for the period of one year from June 2012 to May 2013 in order to understand the physico-chemical properties of sediments samples collected along the Mahim Creek of Mumbai. The annual average pH value of the creek sediments was recorded as 9.22. It is feared that such conditions may increase the alkalinity of Creek water which according to USEPA will increase the physiological stress of many aquatic species resulting in decreased reproduction, decreased growth, disease, or death thereby reducing the biological diversity of the Creek. The total organic matter in the creek sediments was found to be maximum of 10.30 % with an annual average concentration of 6.29 %. Although organic matter is a primary source of food for benthic organisms and is important in maintaining a viable ecosystem, too much of organic matter deposited in the sediments will be responsible for depletion in dissolved oxygen content of the creek water causing unpleasant odours and may also increase the rate of eutrophication. From the results it appears that as India moves towards stricter regulation of industrial effluents to control water pollution, greater efforts are required to control the discharge of pollutants into the ecosystems.
EN
The paper deals with monitoring of pollution arising due to oil and surfactants manufacturing industries located along the Dombivali industrial belt of Mumbai, India. The study was carried for the period of one year from June, 2012 to May, 2013 to study the level of toxic heavy metals and the physico-chemical properties of waste water effluents discharged from the above industries. The maximum concentration of majority of heavy metals like Cu, Ni, Cr, Pb and Fe were recorded as 13.48, 3.90, 13.30, 1.75 and 15.89 ppm respectively, which were above the tolerable limit set for inland surface water. The maximum pH and conductivity values of the industrial waste water effluent were recorded as 10.05 and 27800 μmhos/cm respectively. The majority of physico-chemical parameters like chloride, cyanide, phosphate and total solid content were found to be maximum in the month of March having the respective values of 2340, 0.09, 35.2 and 8755 ppm. The effluent samples collected in the month of May was found to have low DO content of 3.33 ppm and high BOD content of 643 ppm. The alkalinity and COD values were reported to be maximum of 1988 and 4410 ppm respectively in the month of February. The hardness and salinity content was reported maximum of 131 and 5.76 ppm during the month of December and June respectively. The results of present research work indicates that time has come to move towards ecosystem specific discharge standards to maintain the health and productivity of natural resources on which the majority of Indians are dependent.
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.
EN
The paper deals with monitoring of pollution arising due to textile based industries located along the Dombivali industrial belt of Mumbai, India. The study was carried for the period of one year from June, 2012 to May, 2013 to study the level of toxic heavy metals and the physico-chemical properties of waste water effluents discharged from the above industries. The concentration level of majority of toxic heavy metals like Cu, Ni, Pb, and Zn were reported to be maximum of 45.58, 2.00, 2.06 and 9.20 ppm respectively in the month of April, while Cr and Fe concentration levels were found to be 2.50 and 55.30 ppm in the month of March. The effluent samples collected in the month of July was reported to show high BOD content of 564 ppm, while COD content was maximum of 2436 ppm in the month of October. The effluent samples collected in the month of January was having very low DO content of 3.21 ppm and high cyanide content of 0.09 ppm. The alkalinity, hardness and chloride content were maximum of 2158, 198 and 2765 ppm respectively in the effluent samples collected in the month of February. The effluents were having high total solid content of 8269 ppm during the month of April, while the salinity and phosphate contents were reported high of 5.64 and 125.70 ppm during the month of May. It was observed that the concentration level of majority of toxic heavy metals and the values of various physico-chemical parameters were above the tolerable limit set for inland surface water. The present experimental data on environmental risk assessment studies due to textile industries may be regarded as an aid towards a better understanding of the problem arising due to such industries. There is a need to convey the message that prevention of adverse health effects and promotion of health are profitable investments for employers and employees as a support to a sustainable development of economics.
EN
In the present investigation, attempts were made to understand the difference in bromide ion selectivity of the two closely related anion exchange resins Auchlite ARA-9366 and Auchlite A-378 in chloride form. The selectivity difference was predicted based on the thermodynamic equilibrium constants and enthalpy values of Clˉ/Brˉ ion exchange reactions performed by using the two resins. During Clˉ/Brˉ exchange reactions, with rise in temperature from 30.0 °C to 45.0 °C, the equilibrium constant (K) values were observed to decreases from 8.15x10-2 to 6.06x10-2 for Auchlite ARA-9366 resins and from 2.16x10-2 to 1.10x10-2 for Auchlite A-378 resins. The decrease in K values with rise in temperature, indicate exothermic ion exchange reactions having enthalpy values of -36.14 and -18.38 kJ/mol respectively. The high K and low enthalpy values obtained for Auchlite ARA-9366 resins indicate their greater selectivity for the bromide ions in the solution as compared to Auchlite A-378 resins.
14
Content available Study of Toxic Heavy Metals in Mahim Creek of Mumbai
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EN
The present study was performed for the period of one year from June 2012 to May 2013 in order to understand the level of toxic heavy metals in the water of Mahim Creek near Mumbai. It was observed that the annual average concentration of heavy metals like Pb, Cd, Cr, Fe, Zn, Cu and Ni and Hg was found to be 0.68, 0.28, 0.15, 0.04, 2.93, 0.64, 1.29 and 0.31 ppm respectively. The average concentrations of Hg and Pb were found to be above the maximum permissible limit of 0.01 ppm and 0.1 ppm respectively set for inland surface water by Central Pollution Control Board (CPCB) of India. The results suggest that there is a need to have such regular scientific monitoring for longer time period in order to understand the variation in level of these toxic heavy metals discharged in to the creek water. It is feared that the existing problem if ignored may increase the pollution problem of the creek due to the toxic heavy metals resulting in threat to the biological life of an aquatic ecosystem. From the results of the present investigation it seems that the time has come to move towards ecosystem specific discharge standards to maintain the health and productivity of natural resources on which the majority of human population is dependent.
EN
The paper deals with predicting the iodide ion selectivity of nuclear and non-nuclear grade anion exchange resins. The ionic selectivity prediction was made on the basis of thermodynamic data of Clˉ/I ˉ ion exchange reaction. It was observed that with rise in temperature from 30.0 °C to 45.0 °C, the equilibrium constant (K) values were observed to decreases from 59.77x10-2 to 23.77x10-2 for Auchlite ARA-9366 resins and from 9.01x10-2 to 4.05x10-2 for Auchlite A-378 resins. The decrease in K values with rise in temperature, indicate exothermic ion exchange reactions having enthalpy values of -47.87 and -39.51 kJ/mol respectively. The high K and low enthalpy values obtained for Auchlite ARA-9366 resins indicate their greater selectivity for the iodide ions in the solution as compared to Auchlite A-378 resins, when both the resins are present in chloride form.
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.
EN
The paper deals with monitoring of pollution arising due to pharmaceutical based industries located along the Dombivali industrial belt of Mumbai, India. The study was carried for the period of one year from June, 2012 to May, 2013 to study the level of toxic heavy metals and the physico-chemical properties of waste water effluents discharged from the above industries. The concentration level of majority of toxic heavy metals like Cu, Cr, Pb, Fe and Zn were found to be maximum of 14.06, 0.57, 0.42, 18.93 and 3.31 ppm respectively in the month of February, while Ni concentration was found to be maximum of 0.43 ppm in the month of June. The pH and BOD values were reported to be maximum of 12.54 and 546 ppm respectively in the month of October. The conductivity and total solid content was found to be maximum of 27400 μmhos/cm and 9401 ppm respectively in the month of June. The cyanide content was maximum of 0.13 ppm in the month of April. The alkalinity, hardness, salinity, chloride, phosphate and COD content was reported maximum of 852, 694, 10.36, 4821, 46.32 and 1271 ppm respectively in the month of February. The DO content was found to be minimum of 3.00 ppm in the month of February. It was observed that the level of many of these toxic heavy metals except Zn and various physico-chemical parameters were above the tolerable limit set for inland surface water. From the results of the present investigation it seems that the time has come to move towards ecosystem specific discharge standards to maintain the health and productivity of natural resources on which the majority of Indians are dependent.
EN
The paper deals with monitoring of pollution arising due to metallurgical industries located along the Dombivali industrial belt of Mumbai, India. The study was carried for the period of one year from June, 2012 to May, 2013 to study the level of toxic heavy metals and the physico-chemical properties of waste water effluents discharged from the above industries. The concentration levels of Cu, Ni, Cr, Pb, Fe and Zn were found to be maximum of 41.00, 1.47, 5.97, 2.55, 46.86 and 12.97 ppm respectively during winter and summer seasons starting from December to May. The pH value was found to be maximum of 10.30 in the month of February, while the conductivity was found to be maximum of 25067 μmhos/cm in the month of July. The majority of physco-chemical parameters like salinity, chloride content, and total solids (TS) were observed to be maximum in the month of June having values of 6.32, 2411 and 20738 ppm respectively. The high cyanide (0.09 ppm), phosphate (117.21 ppm), COD (13640 ppm) and low DO content of 5.79 ppm were observed in the effluents released during the month of February. The alkalinity content in the effluent was maximum of 1395 ppm in the month of May. The hardness and BOD values of the effluents were reported maximum of 490 and 557 ppm in the month of October. From the results of the present investigation it seems that the time has come to implement proper effluent water treatment techniques and enforcement of pollution control by the regulatory authority on the indiscriminate discharge of industrial wastewater into water bodies.
EN
In the present paper attempts are made to understand the selectivity of nuclear grade cation exchange resin Indion-223 in H+ form towards Ca2+ and Mg2+ bivalent ions in the solution based on thermodynamic concept. It was observed that with rise in temperature the equilibrium constant K values for H+/Ca2+ uni-bivalet ion exchange reactions increases from 0.000397 to 0.000639. Similarly for H+/Mg2+ uni-bivalet ion exchange reactions the equilibrium constant K values increases from 0.000177 to 0.000333. The increase in equilibrium constant values with rise in temperature indicate endothermic ion exchange reactions having the enthalpy change values of 38.92 and 51.46 kJ/ mol respectively. The difference in K values and enthalpy values were used to predict the selectivity behaviour of the resin towards the Ca2+ and Mg2+ bivalent ions in the solution. The thermodynamic concept of the present study can be applied to understand the selectivity behaviour of different nuclear as well as non-nuclear grade resins towards wide range of ionic species present in the exchanging liquid medium.
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