Determination of total sulphur in ethanol by reduction using Raney nickel and detection by cathodic stripping voltammetry

Abstract

A procedure for the determination of total sulphur in ethanol by reduction of the sulphur compounds to sulphide using Raney nickel, conversion to H₂S and detection by differential-pulse cathodic stripping voltammetry (DPCSV) is presented. The supporting electrolyte that gave the best results was a sulphide antioxidant buffer (SAOB II, 10%). The calibration graph covered the concentration range 1–40 p.p.b., and the method could be used for ethanol samples with sulphur contents ranging from 15 ng g^–1 to 20 µg g^–1. The precision and accuracy of the method compare well with values in the literature.