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Application of Plasticized Cellulose Triacetate Membranes for Recovery and Separation of Cerium(III) and Lanthanum(III)

Pospiech Beata, Makowka Adam

Autex Research Journal

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2022

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Vol. 22, no. 3

312--317

EN

This work explains the application of plasticized cellulose triacetate (CTA) membranes with Cyanex 272 di(2,4,4-(trimethylpentyl)phosphinic acid) and Cyanex 301 (di(2,4,4-trimethylpentyl)dithiophosphinic acid) as the ion carriers of lanthanum(III) and cerium(III). CTA is used as a support for the preparation of polymer inclusion membrane (PIM). This membrane separates the aqueous source phase containing metal ions and the receiving phase. 1M H2SO4 is applied as the receiving phase in this process. The separation properties of the plasticized membranes with Cyanex 272 and Cyanex 301 are compared. The results show that the transport of cerium(III) through PIM with Cyanex 272 is more efficient and selective than lanthanum(III).

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Synthesis of Polymer Inclusion Membranes based on Cellulose Triacetate for Recovery of Lanthanum(III) from Aqueous Solutions

Makowka Adam, Pospiech Beata

Autex Research Journal

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2019

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Vol. 19, no. 3

288--292

EN

Polymer inclusion membrane (PIM) containing cellulose triacetate (CTA) as a polymer matrix and 2-nitrophenyl octyl ether (NPOE) as a plasticizer was developed. This membrane also contained di(2-ethylhexyl)phosphoric acid (D2EHPA) and tributyl phosphate (TBP) as the carriers of metal ions. The facilitated transport of lanthanum(III) from aqueous nitrate(V) solutions across PIM was studied. It was observed that metal ions were transported from the source phase into 2M H2SO4 as the receiving phase. The transport through PIM with D2EHPA as the ion carrier was found as the more effective method of lanthanum(III) removal from the aqueous solution than transport through PIM with TBP as the ion carrier.

3

The Mediatory Activity of Ce(IV)/Ce(III) Redox System Immobilized in NafionŽ Film on Glassy Carbon

Domagała S., Dziegieć J., Cichomski M., Grobelny J.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 5-6

1049-1061

EN

Properties of the glassy carbon modified with Ce(III) ions immobilized in Nafion film and the catalytic activity of these ions or the catalytic activity of the modified conducting phase in electrochemical oxidation of some hydroquinone, phenylenediamine and 4-hydroxybenzoic acid derivatives were investigated. The redox activity was characterized in aqueous solutions of perchloric acid by cyclic voltammetry. The redox processwas diffusion- limited which can suggest that the cerium(III) ions immobilized in the Nafion multilayer was rate-controlling. The increase of anodic peaks of investigated compounds during oxidation on the modified electrode (GC/Nafion/Ce(III)), and drastic decrease of cathodic peak related to Ce(IV) ions reduction, points to the mediatory activity of these ions. The increase of oxidation currents observed during preparative electrolyses indicates the catalytic properties of the modified conducting phase. The preparative electrooxidation of investigated compounds showed that the 100% conversion of the substrate occurs in the shortest time on glassy carbon modified with Ce(III) ions immobilized in Nafion film. AFMtapping mode phase imaging was used to identify the hydrophobic and hydrophilic regions of Nafion perfluorosulfonate cation exchange membranes. The clusters agglomerates have a range of sizes from 5 to 30 nm.