ION EXCHANGE OF COBALT IONS BY ETS-4 AND ETS-10 MICROPOROUS TITANOSILICATES

2004 ◽  
Vol 3 (3) ◽  
pp. 275-282
Author(s):  
Claudiu Constantin Pavel ◽  
Pierantonio De Luca ◽  
Nicolae Bilba ◽  
Alfonso Nastro
Keyword(s):  
Ion Exchange ◽  
Cobalt Ions

scholarly journals Competitive Heavy Metal Removal from Binary Solution

2020 ◽  
Vol 69 (9-10) ◽  
pp. 465-471
Author(s):  
Anita Bašić ◽  
Mario Nikola Mužek ◽  
Lea Kukoč-Modun ◽  
Sandra Svilović
Keyword(s):  
Heavy Metal ◽  
Ion Exchange ◽  
Metal Removal ◽  
Binary Solution ◽  
Exchange Process ◽  
Heavy Metal Removal ◽  
Cobalt Ions ◽  
Rushton Turbine ◽  
Ion Exchange Process ◽  
Ion Exchange Kinetics

The removal of copper and cobalt ions from binary metal solutions on zeolite NaX by ion exchange process was investigated. Experiments were conducted in unbaffled glass reactor with a Rushton turbine as a stirrer. The dependence of ion exchange kinetics and the amount exchanged were tested using different initial concentrations of metal ions in mixtures. The results obtained indicate that the removal efficiency depends on the initial heavy metal concentrations in binary solutions. Experimental kinetics data were analysed using Ritchie and Weber-Morris models. According to AARD values, the rate in this study was reaction-controlled.

Application of advanced adsorption processes for dissolved organic matter and heavy metal removal from water sources

2015 ◽  
Author(s):  
◽  
A.K.M. Nazmul Hussain
Keyword(s):  
Organic Matter ◽  
Water Treatment ◽  
Ionic Strength ◽  
Ion Exchange ◽  
Molecular Size ◽  
Hematite Nanoparticles ◽  
Cobalt Ions ◽  
Initial Concentration ◽  
Adsorptive Removal ◽  
Trace Compounds

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] The main objective of this research was to develop an improved understanding of natural organic matter (NOM) and heavy metals removal from two water sources: the City of Columbia McBaine Water Treatment Plant and synthetic water samples prepared in the laboratory. Batch experiments were conducted to evaluate the feasibility of utilizing the adsorption process with magnetite, magnetic ion exchange resin (MIEX), and powdered activated carbon (PAC) as adsorbents to reduce the NOM found in natural groundwater. Control and treated samples were studied to determine the removal degree of dissolved organic matter (DOC) and to verify the impact to the formation potential of disinfection by-products (DBPs). There was no clear correlation found between DOC and disinfection byproducts formation potential (THMFP) over the range of DOC values examined in this study. For MIEX applications, this lack of correlation between DOC removal and DBP could be due to partial dissolution of organic components from MIEX itself. The research provides a framework for using adsorption for the removal of NOM and control of DBP. The presence of common groundwater constituents, such as iron, was found to adversely impact the adsorption capacity of NOM onto MIEX. Possible reasons may include- blocking of the ion-exchange sites on MIEX, and the formation of NOM-Fe complexes that may possess different sorption characteristics from pure NOM. The effects of iron in both Fe2+ and Fe3+ states on the adsorption of NOM onto MIEX were evaluated. The removals of TOCs were found to be higher in oxic conditions whereas the removals of UV254s were found to be higher in anoxic conditions. In oxic conditions, MIEX was capable of removing both NOM and iron effectively when coexisting in raw water. Iron could compete with NOM for exchange sites on MIEX at high dosages (>4 ml/L), which in turn could decrease the NOM removal rate. In anoxic conditions, similar removal patterns were observed as those in oxic conditions, except that MIEX adsorbed less iron with increasing iron content in the water samples. The extent of competitive adsorption was dependent on the initial concentration of trace compounds, the initial concentration of NOM, the molecular size of trace compounds, the molecular size distribution of NOM molecules, and the type and dosage of adsorbents. Experiments were also conducted to study the effects of pH, ionic strength and hematite nanoparticles dosage on the adsorptive removal of Co2+ from aqueous solution. It was observed that adsorption was enhanced in neutral pH conditions, comparing to acidic condition and irrespective of ionic strength. Freundlich models were capable of representing the data more satisfactorily than the Langmuir models. The co-ions removed Co in the order Pb2+> Cu2+ >HA. Hematite nanoparticles derived from ferroxane-AA were deposited on porous alumina tubes to develop tubular ceramic membrane for the removal of Co2+. Ferroane-AA loading on ceramic tube was found to be very low; 0.5 g of ferroxane-AA loaded only 1% and 2.0 g of ferroxane-AA loaded 0.7%. The regeneration process was tested for 4 washing cycles without membrane damage. The results of this study indicate that, with the adsorptive removal of cobalt ions from natural groundwater and the ability to adsorb multiple metal ions simultaneously, hematite nanoparticles may offer a potential and suitable remediation method for the removal of cobalt ions. The ferroxane-AA fabrication process takes place in an aqueous environment, does not involve the use of hazardous substances, and has low energy consumption due to the low firing temperature of the ceramic tube. Furthermore, the generation of liquid wastes on site can be avoided during operation. The membranes can be re-used after washing with a basic solution. The materials can be processed for regeneration in a centralized treatment facility for improved liquid waste management. Its compact and user-friendly design allows it to be deployed at the point of use, while it is also flexible to adapt to a larger scale, suitable for water treatment plants.

Spectrochemical Determination of Nanogram Amounts of Cobalt in Blood Using the Copper-Spark Method

1968 ◽  
Vol 22 (3) ◽  
pp. 183-187 ◽  
Author(s):  
A. M. Kabiel ◽  
Z. G. Hanna ◽  
Y. S. Youssif
Keyword(s):  
Trace Elements ◽  
Ion Exchange ◽  
Human Blood ◽  
Limit Of Detection ◽  
Minor Constituent ◽  
Cobalt Ions ◽  
Concentration Method

The superiority of spectrographic methods in the estimation of cobalt, the minor constituent in human blood, is pointed out. The main advantages are speed, sensitivity, and certainty in the identification of the trace elements being determined. The analysis is carried out using an ion-exchange concentration method to separate nanograms of cobalt ions from the interfering extraneous elements, followed by a copper spark method which proved to be valuable in reducing the limit of detection. Illustrated examples are given of the kinds of work to which the method is applied.

Embedding Procedure for Water Swollen Samples

1970 ◽  
Vol 28 ◽  
pp. 504-505
Author(s):  
Ann M. Thomas ◽  
Virginia Shemeley
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Ion Exchange ◽  
Structural Changes ◽  
Cross Linking ◽  
Ion Exchange Resins ◽  
Transmission Electron ◽  
First Pass ◽  
Exchange Resins

Those samples which swell rapidly when exposed to water are, at best, difficult to section for transmission electron microscopy. Some materials literally burst out of the embedding block with the first pass by the knife, and even the most rapid cutting cycle produces sections of limited value. Many ion exchange resins swell in water; some undergo irreversible structural changes when dried. We developed our embedding procedure to handle this type of sample, but it should be applicable to many materials that present similar sectioning difficulties.The purpose of our embedding procedure is to build up a cross-linking network throughout the sample, while it is in a water swollen state. Our procedure was suggested to us by the work of Rosenberg, where he mentioned the formation of a tridimensional structure by the polymerization of the GMA biproduct, triglycol dimethacrylate.

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