Determination of sulfur dioxide in vitriol plant wastewater by using a polyNiMe4TAA electrochemically modified Pt microelectrode

Abstract

A Pt microelectrode modified with nickel(II) polytetramethyldibenzo[b,i]tetraaza[14]annulene was prepared by electropolymerization of nickel(II) tetramethyldibenzo[b,i]tetraaza[14]annulene monomers and applied to determine sulfur dioxide in vitriol plant wastewater. For determination of SO₂ with this electrochemically modified Pt microelectrode, the linear range was from 9.6 × 10⁻⁶ to 2.4 × 10⁻⁴ mol L⁻¹, the sensitivity was 1.8 × 10⁻⁴ A L mol⁻¹, the detection limit was calculated to be 4.8 × 10⁻⁶ mol L⁻¹ (S/N = 3), the response time was less than 20 s and the relative standard deviation was found to be 2.1% on analyzing 4.8 × 10⁻⁵ mol L⁻¹ SO₂ solution repeatedly (n = 7). These results demonstrated good accuracy compared with those obtained by the conventional iodimetric method.