Use of a novel coupled-oxidation tubular reactor (COTR)/ NTP-DBD catalytic plasma in a synergistic electro-catalysis system for odorous mercaptans degradation.

In this work, a novel coupled-oxidation tubular reactor (COTR)/non-thermal dielectric barrier discharge (NTP-DBD) catalytic plasma in a synergistic electro-catalysis system was investigated for odorous mercaptans decomposition. In order to enhance the degradation efficiency of electro-oxidation, a novel enhanced Ti/PbO electro-catalytic tubular reactor prepared by using flow dynamic electrodeposition was designed and applied as pretreatment process for CHSNa wastewater. The results indicated that the optimal condition was 7 mA cm of current density, 10 g L of initial concentration of CHSNa, 9.0 of pH and 5.0 g L of electrolyte concentration. Addition of Fe and HO and mechanism of COTR system were first put forward. The target species CHSNa were removed over 90% by this process. In order to treat the CHSH effusion which was co-produced with CHSNa aqueous solution, the technology of NTP-DBD catalytic plasma reactor followed by a chemical absorption has been developed. MSH could be removed over 95% under the condition of 2 s of residence time, 15 kV of output voltage with oxygen concentration of 9%. Moreover, the synthetic Ni-doped AC catalyst had the best performance under 0.7 mmol g of nickel loading. The conclusion was the energetic electrons generated in the DBD reactor played a key role on the removal of MSH, and the major decomposition products of MSH were detected as CHSSCH, SO and NO. Moreover, the gaseous products in the plasma exhaust could be absorbed and fixed by the subsequent aqueous NaOH solution.