Degradation of DMSO by ozone-based advanced oxidation processes

Area of Science:

• Environmental Chemistry
• Water Treatment Technologies

Background:

• Dimethyl sulfoxide (DMSO) is a common industrial solvent.
• Effective removal of DMSO from wastewater is crucial for environmental protection.

Purpose of the Study:

• To investigate the oxidation of DMSO using conventional ozonation.
• To evaluate the efficacy of advanced oxidation processes (AOPs) like O(3)/UV, O(3)/H(2)O(2), and UV/H(2)O(2) for DMSO degradation.
• To compare the degradation pathways and mineralization rates.

Main Methods:

• Conventional ozonation of DMSO.
• Application of O(3)/UV, O(3)/H(2)O(2), and UV/H(2)O(2) processes.
• Identification of major degradation products (methanesulfinate, methanesulfonate, formaldehyde, formic acid).
• Evaluation of reaction rate constants and mineralization efficiency.
• Analysis of sulfate ion formation.

Main Results:

• Methanesulfonate was identified as a persistent intermediate, hindering complete mineralization.
• The rate constant for ozone reaction with DMSO was determined as 0.4162 M(-1)S(-1).
• Advanced oxidation processes demonstrated more significant organic degradation than TOC removal.
• Sulfate ion formation was observed in all AOPs.

Conclusions:

• Ozonation and ozone-based AOPs are effective for DMSO removal from wastewater.
• Further research may be needed to address the persistence of methanesulfonate for complete mineralization.