Polymer Ion-Exchangers Modified with Zirconium Hydrophosphate for Removal of Cd²⁺ Ions from Diluted Solutions

Abstract

Hybrid ion-exchangers have been synthesized by modification of strongly acidic cation-exchange resin with zirconium hydrophosphate. The samples were investigated with scanning and transmission electron microscopy and standard contact porosimetry. Single nanoparticles and their aggregates have been found in the polymer. The nanoparticles in transport pores increase the electrical conductivity of ion-exchanger from 0.21 to 0.65 Ohm⁻¹ m⁻¹. The diffusion coefficient of Cd²⁺ ions reaches 2.43 × 10⁻¹¹ m² s⁻¹ for initial resin and (2.50–4.34) × 10⁻¹¹ m² s⁻¹ for nanocomposites. The inorganic constituent improves Cd²⁺ recovery from a solution, which contains also Ca²⁺ and Mg²⁺. The degree of Cd²⁺ removal is 18% for non-modified resin and 99% for the sample containing 38 mass% zirconium phosphate.

Keywords:

• cation-exchange resin and membrane
• nanocomposite
• organic-inorganic ion-exchanger
• standard contact porosimetry
• zirconium phosphate

ACKNOWLEDGEMENTS

The work was supported by projects within the framework of programs supported by the government of Ukraine “Nanotechnologies and Nanomaterials” (grant No. 6.22.1.7) and the NAS of Ukraine “Problems of stabile development, rational nature management and environmental saving” (grant N 30-11).

Notes

The data correspond to break-through capacity towards Cd²⁺.