Synergistic removal of sulphur-containing malodourous gases via peroxydisulfate activation in three-dimensional electrode system

A novel technology for peroxydisulfate (PDS) activation in a three-dimensional electrode system (3DES) was employed to purify sulphur-containing malodourous gases; the technical parameters of the process were optimised and the pathway of sulphur-containing malodourous substances was investigated. In 3DES, reactive substances such as SO4 (circle) -, O-1(2), and circle OH were markedly higher, the SO4 (circle-) radicals played a significant role in the context of sulphur-containing malodourous gases, and the conversion of CH3SH and CS2 was more complete. The CH3SH in the inlet gas was completely removed within 180 min, the CS2 removal was approximately 100% before 60 min, and it then tended to decline gradually. As H2S and NH3 coexisted in the inlet gas, there was no significant effect on odour removal, and the discarded absorption solution could be used to prepare nitrogen fertiliser as the efficiency of odour removal decreased. The particle electrode in 3DES not only promoted the transfer of insoluble gases into the absorption solution but also enhanced PDS activation. Consequently, the catalytic oxidation performance was greatly improved. A conversion pathway was proposed to explain the transformation of sulphur-containing components such as CH3SH and CS2. This study provides new insights for the removal of malodourous pollutants.