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Improvement of Selectivity of RALEX-CM Membranes via Modification by Ceria with a Functionalized Surface.

ABSTRACT: Ion exchange membranes are widely used for water treatment and ion separation by electrodialysis. One of the ways to increase the efficiency of industrial membranes is their modification with various dopants. To improve the membrane permselectivity, a simple strategy of the membrane surface modification was proposed. Heterogeneous RALEX-CM membranes were surface-modified by ceria with a phosphate-functionalized surface. Despite a decrease in ionic conductivity of the prepared composite membranes, their cation transport numbers slightly increase. Moreover, the modified membranes show a threefold increase in Ca²⁺/Na⁺ permselectivity (from 2.1 to 6.1) at low current densities.

SUBMITTER: Stenina I

PROVIDER: S-EPMC9919321 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature

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Improvement of Selectivity of RALEX-CM Membranes via Modification by Ceria with a Functionalized Surface.

Stenina Irina I Yurova Polina P Achoh Aslan A Zabolotsky Victor V Wu Liang L Yaroslavtsev Andrey A

Polymers 20230127 3

Ion exchange membranes are widely used for water treatment and ion separation by electrodialysis. One of the ways to increase the efficiency of industrial membranes is their modification with various dopants. To improve the membrane permselectivity, a simple strategy of the membrane surface modification was proposed. Heterogeneous RALEX-CM membranes were surface-modified by ceria with a phosphate-functionalized surface. Despite a decrease in ionic conductivity of the prepared composite membranes ...[more]

PMID: 36771946

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