Selective removal of Cd(II) ion using synthesised Poly(o-anisidine)–Sn(IV)silicophosphate nanocomposite

Abstract

ABSTRACT A nanocomposite cation exchanger, poly(o-anisidine)–Sn(IV)silicophosphate, was synthesised using the sol-gel method by the incorporation of Sn(IV)silicophosphate into the poly(o-anisidine) matrix. The physicochemical properties were investigated using FTIR, simultaneous TGA-DTA, SEM and TEM. Characterisation of the polymer-based nanocomposite has shown granulometric nature of the composite with uniform surface morphology and appreciable thermal and chemical stability. The ion-exchange capacity (Na+ ion) of the cation exchanger synthesised at an optimum pH of 0.75 was found to be 1.92 meq g−1. The nanocomposite can withstand temperature as high as 400 with retention of 81.8% of its initial ion-exchange capacity and a mere weight loss of 11.2%. Metal sorption study carried out in different solvent shows the selectivity of the nanocomposite for Cd2+ and Th4+ in all solvent media. Analytically important quantitative binary separations of metal ions were achieved using the synthesised cation exchanger with recovery almost 99.0%. The limit of detection (LOD) and limit of quantification (LOQ) for Cd2+ were found to be 1.60 µg L−1 and 5.33 µg L−1 respectively. Selective removal of hazardous Cd2+ from the industrial effluent reflects the potential utility of the synthesised nanocomposite in environmental pollution control and wastewater treatment.