Nanoparticles of zirconium hydrophosphate framed with a weakly-acidic cation-exchange polymer

Weakly acidic cation exchange resin was modified with nanoparticles of zirconium hydrophosphate. The materials were investigated with methods of standard contact porosimetry and transmission electron microscopy. Both non-aggregated nanoparticles (4–15 nm) and larger formations (from 250 nm to several microns) have been found. Single particles in clusters and channels of the polymer depress dissociation of carboxylic groups due to counter-ions (H + ) in electric double layer around the particles. This causes transformation of porous structure of the polymer: the contribution of micropores to total porosity increases. These additional selective sites provide stronger interaction of Brilliant Green molecules with the surface in comparison with the pristine polymer. Removal of the dye from deionized water and Ni(II) ions from water containing also hardness ions was studied under dynamic conditions. The composite shows higher break-through capacity than that of the pristine resin. The modifier also facilitates regeneration of the weakly acidic ion-exchanger.