scholarly journals Potentiometric Sensor for Gadolinium(III) Ion Based on Zirconium(IV) Tungstophosphate as an Electroactive Material

2009 ◽  
Vol 6 (4) ◽  
pp. 1139-1149 ◽  
Author(s):  
Harish K. Sharma ◽  
Nadeem Sharma
Keyword(s):  
Ion Exchange ◽  
Epoxy Resin ◽  
Aqueous Media ◽  
Earth Metal ◽  
Potential Method ◽  
Selectivity Coefficient ◽  
Exchange Capacity ◽  
Ion Exchange Capacity ◽  
Electroactive Material ◽  
Wide Range

A new inorganic ion exchanger has been synthesized namely Zirconium(IV) tungstophosphate [ZrWP]. The synthesized exchanger was characterized using ion exchange capacity and distribution coefficient (Kd). For further studies, exchanger with 0.35 meq/g ion-exchange capacity was selected. Electrochemical studies were carried out on the ion exchange membranes using epoxy resin as a binder. In case of ZrWP, the membrane having the composition; Zirconium(IV) tugstophosphate (40%) and epoxy resin (60%) exhibits best performance. The membrane works well over a wide range of concentration from 1×10-5to 1×10-1M of Gd(III) ion with an over- Nernstian slope of 30 mv/ decade. The response time of the sensor is 15 seconds. For this membrane, effect of internal solution has been studied and the electrode was successfully used in partially non-aqueous media too. Fixed interference method and matched potential method has been used for determining selectivity coefficient with respect to alkali, alkaline earth, some transition and rare earth metal ions that are normally present along with Gd(III) in its ores. The electrode can be used in the pH range 4.0-10.0 for 10-1M and 3.0-7.0 for 10-2M concentration of target ion. These sensors have been used as indicator electrodes in the potentiometric titration of Gd(III) ion against EDTA and oxalic acid.

scholarly journals Modified Phillipsite as a Novel Ion-Exchanger for Potassium Extraction from Seawater

2019 ◽  
Vol 25 (4) ◽  
pp. 441-445
Author(s):  
Chunxia MENG ◽  
Jin HOU
Keyword(s):  
Hydrothermal Synthesis ◽  
Ion Exchange ◽  
Average Particle Size ◽  
Selectivity Coefficient ◽  
Exchange Capacity ◽  
Ion Exchanger ◽  
Average Particle ◽  
Mixed Solution ◽  
Ion Exchange Capacity ◽  
X Ray

Template-free preparation of phillipsite as a novel K+ ion-exchanger was studied systematically by hydrothermal synthesis. The alkalinity, dosage of water glass, dosage of H2O, aging time, reaction temperature and time of hydrothermal synthesis were discussed in detail. The optimized material obtained about phillipsite through the synthesis and testing methods was performed. The K+ ion-exchange capacity and selectivity coefficient were tested. The molar composition for preparing high performance phillipsite obtained was 2K2O:18SiO2:Al2O3:510H2O by optimizing synthetic conditions. The K+ ion-exchange capacity of phillipsite was 57.3 mg/g in seawater. The K+ selectivity coefficient was 88.6 in an equimolar K+ and Na+ mixed solution. Phillipsite can selectively capture K+ over other ions, and therefore can be used for potassium extraction selectively from seawater. Phillipsite was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). The XRD pattern indicated that the synthetic zeolite was phillipsite. The phillipsite particles exhibited cross-like shape and the average particle size was about 2.5 μm. The synthetic phillipsite was mainly consisted of Si, Al, K and O elements.

scholarly journals UPTAKE ABILITY OF ZEOLITIC ROCK FROM SOUTH XEROVOUNI, AVDELLA, EVROS, HELLAS

2017 ◽  
Vol 43 (5) ◽  
pp. 2762
Author(s):  
E. Tzamos ◽  
A. Filippidis ◽  
N. Kantiranis ◽  
C. Sikalidis ◽  
A. Tsirambidis ◽  
...  
Keyword(s):  
Ion Exchange ◽  
Clay Minerals ◽  
Total Content ◽  
Exchange Capacity ◽  
Small Extent ◽  
Ion Exchange Capacity ◽  
Rock Samples ◽  
Wide Range ◽  
Type Zeolite ◽  
Positive Correlations

Zeolitic rock samples from South Xerovouni contain on average, 57 wt.% HEU type zeolite, 6 wt.% clay minerals, 3 wt.% mica (total of 66 wt.% microporous minerals), 19 wt.% feldspars, 10 wt.% cristobalite and 5 wt.% quartz (total of 34 wt.% non-microporous minerals). Chemically the zeolitic rock consists mainly of 69.9 wt.% SiO2, 13.2 wt.% Al2O3, 1.2 wt.% Fe2O3t, 1.0 wt.% MgO, 3.0 wt.% CaO, 1.5 wt.% Na2O and 2.2 wt.% K2O. The zeolitic rock shows an average ammonia ion exchange capacity of 150 meq/100g. HEU-type zeolite accounts for the most of the uptake ability, while clay minerals and mica contribute to a relative small extent only. The uptake ability of the five zeolitic rock samples showed positive correlations with the content of HEU-type zeolite as well as with the total content of microporous minerals (zeolite + mica + clay minerals). Such materials could be used in a wide range and scale of agricultural, aquacultural, and environmental applications.

Equilibrium Sorptions in Heterogeneous Ion Exchange Membranes

1992 ◽  
Vol 57 (9) ◽  
pp. 1905-1914
Author(s):  
Miroslav Bleha ◽  
Věra Šumberová
Keyword(s):  
Experimental Data ◽  
Ion Exchange ◽  
Total Content ◽  
Distribution Coefficients ◽  
Exchange Capacity ◽  
Ion Exchange Membranes ◽  
Ion Exchange Capacity ◽  
Equilibrium Sorption ◽  
Inhomogeneity Factor

The equilibrium sorption of uni-univalent electrolytes (NaCl, KCl) in heterogeneous cation exchange membranes with various contents of the ion exchange component and in ion exchange membranes Ralex was investigated. Using experimental data which express the concentration dependence of equilibrium sorption, validity of the Donnan relation for the systems under investigation was tested and values of the Glueckauf inhomogeneity factor for Ralex membranes were determined. Determination of the equilibrium sorption allows the effect of the total content of internal water and of the ion-exchange capacity on the distribution coefficients of the electrolyte to be determined.

The Synthesis and Ion-Exchange Property of Inorganic Material Mg1.5Mn0.5Ti0.75O4

2012 ◽  
Vol 511 ◽  
pp. 105-108
Author(s):  
Jin He Jiang
Keyword(s):  
Ion Exchange ◽  
Inorganic Material ◽  
Exchange Capacity ◽  
Exchange Property ◽  
Insertion Reaction ◽  
Ion Exchange Capacity ◽  
X Ray ◽  
Thermal Crystallization ◽  
Crystallization Method ◽  
Saturation Capacity

Mg1.5Mn0.5Ti0.75O4 was prepared by a coprecipitation/thermal crystallization method. The extraction/insertion reaction with this material was investigation by X-ray, saturation capacity of exchange, and Kd measurement. The acid treatments of Mg1.5Mn0.5Ti0.75O4 caused Mg2+ extractions of more than 72%, while the dissolutions of Mn4+ and Ti4+ were less than 8.2%. The results showed that the Li+ extraction/insertion be progressed mainly by an ion-exchange mechanism. The acid treated samples had an ion exchange capacity of 10.6mmol/g for Li+.

scholarly journals Polymer Electrolyte Membranes Based on Nafion and a Superacidic Inorganic Additive for Fuel Cell Applications

Polymers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 914 ◽  
Author(s):  
Lucia Mazzapioda ◽  
Stefania Panero ◽  
Maria Assunta Navarra
Keyword(s):  
Fuel Cell ◽  
Ion Exchange ◽  
Proton Exchange Membrane ◽  
Sol Gel ◽  
Composite Membranes ◽  
Exchange Capacity ◽  
Proton Exchange ◽  
Thermal Transitions ◽  
Ion Exchange Capacity ◽  
Electrolyte Membranes

Nafion composite membranes, containing different amounts of mesoporous sulfated titanium oxide (TiO2-SO4) were prepared by solvent-casting and tested in proton exchange membrane fuel cells (PEMFCs), operating at very low humidification levels. The TiO2-SO4 additive was originally synthesized by a sol-gel method and characterized through x-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and ion exchange capacity (IEC). Peculiar properties of the composite membranes, such as the thermal transitions and ion exchange capacity, were investigated and here discussed. When used as an electrolyte in the fuel cell, the composite membrane guaranteed an improvement with respect to bare Nafion systems at 30% relative humidity and 110 °C, exhibiting higher power and current densities.

Clinoptilolite: a possible support material for nitrifying biofilms for effective control of ammonium effluent quality?

2005 ◽  
Vol 51 (11) ◽  
pp. 63-70 ◽  
Author(s):  
H. Inan ◽  
B. Beler Baykal
Keyword(s):  
Ion Exchange ◽  
High Capacity ◽  
Exchange Capacity ◽  
Quality Data ◽  
Ammonium Ion ◽  
Effective Control ◽  
Support Material ◽  
Ion Exchange Capacity ◽  
Effluent Quality ◽  
Peak Loads

Ammonium selective natural zeolite clinoptilolite is suggested as a possible support material for nitrifying biofilms to help improve effluent ammonium quality through its high capacity of ammonium removal in the process of ion exchange. This will especially be helpful in cases where the biofilter receives peak or variable loads routinely or occasionally. At the time of peak loads or shocks of ammonium, ion exchange capacity will provide a buffer for the effluent ammonium quality. Data to support this suggestion is presented.

Adsorption and ion exchange of some groundwater anion contaminants in an amine modified coconut coir

1997 ◽  
Vol 35 (7) ◽  
pp. 89-95 ◽  
Author(s):  
Aloysius U. Baes ◽  
Tetsuji Okuda ◽  
Wataru Nishijima ◽  
Eiji Shoto ◽  
Mitsumasa Okada
Keyword(s):  
Ion Exchange ◽  
Low Cost ◽  
Exchange Capacity ◽  
Batch Adsorption ◽  
Ion Exchange Capacity ◽  
Strong Base ◽  
Chromium Vi ◽  
Freundlich Equation ◽  
Adsorption Data ◽  
Coconut Coir

The adsorption of nitrate, chromium (VI), arsenic (V) and selenium (VI) anions in an amine modified coconut coir (MCC-AE : with secondary and tertiary amine functionality) were studied to determine the capability of this easily prepared and low-cost material in removing typical groundwater anion contaminants. Batch adsorption-ion exchange experiments were conducted using 200 mg MCC-AE, initially containing chloride as the resident anion, and 50 ml of different anion-containing water of varying concentrations. It is presumed, at this low pH, that only SeO42− remained as a divalent anion, while monovalent species H2AsO4− and HCrO4− predominated in their respective exchanging ion solutions. The adsorption data were fitted using the Freundlich equation and maximum adsorption for each anion was estimated using their respective Freundlich equation constants. MCC-AE exhibited preference for divalent Cr (VI) and Se (VI) anions compared with the Cl− resident ion. Maximum As (V) adsorption was 0.086 mmol/g, while maximum adsorption of Cr (VI), NO3− and Se (VI) anions was 0.327 mmol/g, 0.459 mmol/g, and 0.222 mmol/g, respectively. The ion exchange capacity of MCC-AE is estimated, based on its exchange capacity for nitrate, to be within 0.46 mmol of positive charges per gram. Similar adsorption experiments were conducted for comparison using commercial chloride-form Amberlite IRA-900 strong base (quaternary amine functionality) anion exchanger, with an exchange capacity of 4.2 meq/g. Maximum adsorption of the different ions in IRA-900 was about 3 times higher for NO3−, 9 times higher for Se (VI), 10 times higher for As (V) and 9 times higher for Cr (VI), than that in MCC-AE. Differences in the ion exchange behavior of MCC-AE and IRA-900 were probably due to the different amine functionalities in the two exchangers. The results suggest that MCC-AE may be used as a low-cost alternative adsorbent/ion exchanger for treatment of anion contaminants in groundwater.

Sign in / Sign up

Export Citation Format

Share Document