Use of open-circuit pre-concentration of sulphide ion in stripping voltammetry at the parts per billion level of sample

Abstract

A procedure based on open-circuit pre-concentration using a silver disc electrode was developed. This procedure allows sulphide to be pre-concentrated at concentrations ranging from 0 to 40 p.p.b., with subsequent stripping through a linear cathodic potential sweep. The procedure is precise and reliable, with a similar sensitivity to and a better selectivity than those of conventional cathodic-stripping voltammetry. The procedure is useful for monitoring parts per billion levels of sulphide in tap water samples with a precision of 2%.