Electrochemical scission of C–S bond in ethanethiol on a modified β-PbO2 anode in aqueous solution

Specifically odor pollution has attracted more attention over the past several years. Ethanethiol (C2H5SH) is the typical representative due to its lower threshold value. The electrochemical oxidation behavior of ethanethiol solution on a modified β-PbO2 anode with fluoride has been investigated by means of linear sweep voltammetry (LSV). The typical voltammograms of LSV demonstrated that ethanethiol could be oxidized on this electrode at very positive potentials. Results of bulk electrolysis showed that ethanethiol could be thoroughly destructed and eliminated within 35 min in phosphate buffer (pH 6.0) under 60 mA/cm2 of current density due to the successive attack of hydroxyl radicals (OH) electrogenerated on the surface of β-PbO2 anode. Acetic acid (CH3COOH) was the main intermediate and could be further mineralized, while sulfur atom in ethanethiol was finally converted to nonodorous sulfate ions (SO42-), implying that high deodorization performance could be achieved. According to the sulfur balance, it could be concluded that the scission of ethanethiol was occurred via starting with hydroxyl radical attack and followed by C–S bond cleavage. This study highlights a promising technology for the clean and safe removal of odorous compounds from industrial effluents and will be beneficial for nuisance reduction.

► C–S bond in ethanethiol was cleaved by hydroxyl radicals electrogenerated. ► Ethanethiol was finally converted to nonodorous sulfate ions and acetic acid. ► Electrochemical oxidation will be the promising alternative for odor abatement.