Fast cathodic stripping voltammetric determination of elemental sulfur in petroleum fuels using renewable mercury film silver based electrode

The cyclic renewable mercury film silver based electrode (Hg(Ag)FE), applied for fast determination of elemental sulfur using differential pulse cathodic stripping voltammetry (DP CSV) is presented. The calibration graph obtained for S(0) is linear from 5 nM (0.16 μg L−1) to 350 nM (11.2 μg L−1) for a preconcentration time of 30 s, with correlation coefficient of 0.9994. For a Hg(Ag)FE with a surface area of 7.1 mm2 the detection limit for a preconcentration time of 60 s is as low as 0.04 μg L−1. The repeatability of the method at a concentration level of the analyte as low as 0.8 μg L−1, expressed as RSD is 3.7% (n = 5). The proposed method was successfully applied and validated by studying the recovery of S(0) from spiked synthetic solutions and real fuel samples.