Analysis of mercury ions in effluents using potentiometric sensor based on nanocomposite cation exchanger Polyaniline–zirconium titanium phosphate

The objective of the present research was to synthesize, characterize and to investigate the efficiency of an advanced class of hybrid nano-composite cation exchanger for the detection of mercury(II) ion in aqueous solution. In the present study the cation exchanger ployaniline–zirconium titanium phosphate (PANI–ZTP) nanocomposite, was synthesized via sol–gel mixing of organic polymer polyaniline (PANI) into the matrices of the inorganic precipitate of zirconium titanium phosphate (ZTP), having extraordinary ion exchange capacity, thus used as electroactive component for the construction of an ion-selective membrane electrode. The proposed electrode shows fairly good discrimination of mercury ion over several other inorganic ions. The membrane electrode was mechanically stable, having wide dynamic range of 10− 10 mol/m3 to 10− 1 mol/m3 of Hg2+ ions, with quick response time and could be operated for at least 4 months without any considerable divergence in the potential response characteristics. The electrode was successfully applied for direct determination of mercury ions in some real sample with satisfactory results and acts as indicator electrode in complexation titrations.

Research Highlights
► Nanocomposite cation-exchangers, i.e. PANI-ZTP was synthesized by sol gel method.
► TEM prove that the prepared cation exchanger PANI-ZTP is a nanocomposite material.
► The nanocomposite cation-exchangers used an ion-selective membrane electrode.
► The working range is 10–10M to 10–1M for Hg2+ions, and could be operated for at least 4 months.
► The electrode was successfully applied for direct determination of mercury ions.