Determination of lead (II) ion by highly selective and sensitive lead (II) membrane electrode based on 2-(((E)-2-((E)-1-(2-hydroxyphenyl) methyliden)hydrazono)metyl)phenol

Abstract

A PVC (poly vinyl chloride) membrane electrode for lead ion based on 2-(((E)-2-((E)-1-(2-hydroxyphenyl)methyliden)hydrazono)metyl)phenol (HMHMP) as a membrane carrier was prepared. This electrode exhibited linear response with Nernstian slope of 29.2 ± 0.2 mV per decade within the concentration range of 2.0 × 10⁻⁷–1.0 × 10⁻¹ M lead ion. The limit of detection, as determined from the intersection of the extrapolated linear segments of the calibration plot, was 8.0 × 10⁻⁸ M. The electrode exhibited high selectivity for Pb (II). The response time of the electrode was about 5–10 s for different concentrations. The electrode is suitable for use in aqueous solutions in a pH range of 5.0–7.5. It was used as an indicator electrode in a titration of Pb (II) with chromate at constant pH. This electrode was used for the determination of lead in ore samples, and the results were in agreement with those obtained with an atomic absorption spectroscopy (AAS) method. Also lead selective electrode was used for monitoring of lead in spiked samples of the Zayanderud River and waste water by the potentiometry technique.

Keywords:

• ion selective electrode
• potentiometry
• lead
• ore sample

Acknowledgements

The authors express their appreciation to the Payam Noor University, Center of Ardakan and Yazd University Research Councils for financial support of this work.