Catalytic ozonation of dimethyl phthalate using Fe₃O₄/multi-wall carbon nanotubes

ABSTRACT

In this paper, Fe₃O₄/multi-wall carbon nanotubes composites were prepared, characterized and used as a catalyst for enhancing the ozonation of dimethyl phthalate (DMP) in aqueous solution. The experimental results showed that DMP degradation and mineralization increased by 26% and 20%, respectively, in catalytic ozonation compared with single ozonation, and more H₂O₂ and organic acids were produced during catalytic ozonation process than single ozonation. The effect of pH, ozone concentration and catalyst dosage on DMP degradation was determined. The addition of tert-butanol and phosphates showed a negative effect on DMP degradation, suggesting that the acidic sites on the catalyst is favorable to ozone decomposition to produce hydroxyl radicals. The possible mechanism for catalytic ozonation of DMP was tentatively proposed. The adsorption of ozone and organics onto the surface of catalyst could improve the DMP degradation.

KEYWORDS:

• Dimethyl phthalate
• catalytic ozonation
• magnetic carbon nanotubes
• degradation
• plasticizer

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The research was supported by the National Natural Science Foundation of China (51338005) and the Program for Changjiang Scholars and Innovative Research Team in University (IRT-13026).