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1

Effect of the type of ion-exchange resin on Mn2+ adsorption in the presence of competing cations

Amengol Bruna P. C., Pires Renata. C., Leão Versiane A.

Physicochemical Problems of Mineral Processing

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2024

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Vol. 60, iss. 2

art. no. 187844

EN

Present in soils, ground and surface waters, manganese is among the most common metals in Earth crust. It is also an essential trace element to the functioning of several enzymes in the human body. However, exposure to high manganese concentrations can also be harmful to humans with psychiatric and motor effects and therefore, manganese concentrations in drinking water and also industrial effluents are regulated. In the current work, the adsorption of Ca2+, Mg2+ and Mn2+ on three different ion-exchange resins: (i) aminophosphonic acid - chelating (Purolite S950), (ii) polyacrylic weak acid cation (Purolite C104E) and (iii) polystyrene strong acid cation (Purolite C100) was investigated. The results revealed that Purolite S950 had the highest Mn2+ uptake (37.9 mg/mL-resin or 0.69 mmol/mLresin) as compared to Ca2+ (3.2 mg/mL-resin or 0.08 mmol/mL-resin) and Mg2+ (~0 mg/mL-resin) and was selected for further kinetics and equilibrium studies. The results indicated Purolite S950 as particularly suited to be applied in the treatment of neutral mine waters with high Mg/Mn ratios. Additionally, Purolite S950 showed a small affinity for Ca2+ and therefore an efficient Mn2+ removal will depend on the Ca/Mn ratio of the mine water under treatment. According to the kinetic analysis, manganese sorption on Purolite S950 was described by the pseudo-second order model (r2 > 0.98) with an activation energy of 6.34 kJ/mol and thus pore-difussion was the rate controlling step of the process. In terms of equilibrium studies, manganese sorption on Purolite S950 followed the Langmuir model with maximum loadings of up to 41.5 mg/mL-resin. The thermodynamic modelling indicated an exothermic process (-85.0 kJ/mol, as standard enthalpy) with a standard entropy of -274 J/mol×K, which was ascribed to the release of two adsorbed H+ ions for each Mn2+ ion taken up from solution.

2

Sorption and reduction of chromiumion ions by the chelating ion exchanger Diaion CR20

Wójcik Grzegorz

Physicochemical Problems of Mineral Processing

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2019

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Vol. 55, iss. 6

1382--1393

EN

The chelating ion exchanger Diaion CR20 was applied for removal of chromium(VI) ions in the pH range from 1.5 to 10 and in the presence of 1 M H2SO4. The speciation analysis was used to predict the reduction process. Reduction of chromium(VI) to chromium (III) was observed during the chromium(VI) ions sorption. The kinetic parameters for the pseudo-first-order and pseudo-second-order, Elovich and intraparticle diffusion models were calculated. The most common three isotherm models: Freundlich, Langmuir and Dubinin-Radushkevich were used to describe chromium(VI) uptake. It was proved that the polyamine groups present in selected ion exchanger are able to sorb both chromium(VI) and (III) ions. The maximal sorption capacity towards chromium(VI) ions was estimated at pH 1.5 – 169.49 mg Cr(VI)/g and 159.31 mg Cr(VI)/g in 1 M H2SO4. Both static and column methods were used in the investigations.

3

Synthesis, characterization and analytical applications of chelating resin containing orcinol

Shah B. A., Shah A. V., Patel N. B, Shah M.

Polish Journal of Chemical Technology

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2012

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Vol. 14, nr 2

88-96

EN

A chelating resin based on Salicylic acid-Formaldehyde copolymer, containing Orcinol (SFO), has been synthesized and characterized on the basis of Elemental Analysis, Particle Size Distribution, FT-IR Analysis, XRD, SEM and Optical Photographs. The Physico-Chemical properties have been studied. This resin is highly stable in acidic and alkaline solutions and has been studied as a chelating sorbent for heavy metal ions and transition metal ions. The Exchange capacity order is Ni(II) > Cu(II) > Zn(II) > Cd(II) > Pb(II). The effect of nature and concentration of different electrolytes on distribution coefficient (Kd) for metal ions have been investigated. Separation of synthetic mixtures containing Cu(II)-Pb(II), Ni(II)-Cd(II) and Brass constituents has been carried out using a column prepared from the synthesized chelating resin. The developed procedure was also tested for the removal of Cd(II) and Pb(II) from natural water of Purna River near by Navsari, Gujarat, India. Keywords

4

Anionity akrylowe modyfikowane SPADNS jako jonity chelatujące do zagęszczania jonów metali

Greluk M., Hubicki Z.

Przemysł Chemiczny

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2011

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T. 90, nr 1

104-111

5

Tetrakis(p-carboxylphenyl)porphyrin as a complexing agent for solid phase extraction of metal ions

Kilian K., Pyrzyńska K.

Chemia Analityczna

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2002

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Vol. 47, No. 3

439-447

EN

Chelating resins prepared by immobilisation of tetrakis(0-carboxy lphenyl)porphyrin (TCPP) on anion exchange resin Amberlite IRA-401 and nonionic sorbent Amberlite XAD-2 were characterised. Their properties such as retention capacity and sorption kinetics were determined. The retention of metal ions (e.g. Cd, Cu, Co, Ni, Pb and Mg) on these chelating resins were studied. For comparison, sorption of metal complexes with TCPP, formed in a solution, was also investigated.

PL

Modyfikacja anionitu Amberlit IRA-401 i niejonowego sorbentu Amberlit XAD-2 za pomocą roztworu tetra(p-karboksyfenylo)porfiryny (TCPP) umożliwiła otrzymanie sorbentów o właściwościach chelatujących. Zbadano powinowactwo jonów metali — Cd, Cu, Co, Ni, Pb i Mg—do otrzymanych zmodyfikowanych sorbentów. Porównawczo sprawdzono możliwość zatężaniajonów metali po przeprowadzeniu reakcji kompleksowaniaz TCPP w roztworze, a następnie sorpcji utworzonych metaloporfiryn.