Catalytic degradation of dinotefuran by dielectric barrier discharge plasma combined with La-doping TiO₂

ABSTRACT

Degradation of neonicotinoid insecticide dinotefuran (DIN) in dielectric barrier discharge (DBD) non-thermal plasma combined with lanthanum-doped titanium dioxide (La-TiO₂) system was investigated. A La-TiO₂ catalyst was prepared by the sol–gel method and characterized by SEM, XRD, and DRS. The effects of various factors (initial concentration, initial pH, input power, and addition of metal ions) on the removal rate of DIN were evaluated. The results indicated that when the initial concentration, input power, initial pH, and Fe²⁺ catalyst ions were 100 mg/L, 150 W, 10.5 and 50 mg/L, respectively, the DIN degradation efficiency was improved to 99.0% by coupling 10 wt% La-TiO₂ at 180 min. La-TiO₂ showed excellent catalytic performance on DIN degradation in a DBD system. The removal rate decreased with the presence of H₂O₂ and a scavenger, manifesting that $\mathrm{H}{\mathrm{O}}^{\bullet }$ plays an imperative role in the degradation process. Furthermore, intermediate products were analyzed by MS and the possible degradation pathway of DIN was proposed.

GRAPHICAL ABSTRACT

KEYWORDS:

• Dielectric barrier discharge
• non-thermal plasma
• dinotefuran
• La-TiO₂
• degradation pathway

Acknowledgment

This work was supported by the National Key Research and Development Plan of China [No. 2018YFC0408006]; the Natural Science Foundation of China [No. 51978386]; and the National Natural Science Foundation of China Joint Fund Project [No. U1906224].

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by National Key Research and Development Plan of China [No. 2018YFC0408006]; Natural Science Foundation of China [No. 51978386]; National Natural Science Foundation of China Joint Fund Project [No. U1906224].