Abatement of spinosad and indoxacarb residues in pure water by photocatalytic treatment using binary and ternary oxides of Zn and Ti

• Published in: Environmental science and pollution research international Vol. 21; no. 21; pp. 12143 - 12153
• Main Authors: Fenoll, J, Vela, N, Garrido, I, Pérez-Lucas, G, Navarro, S
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01-11-2014; Springer Berlin Heidelberg; Springer Nature B.V
• Subjects: active ingredients; Advanced Oxidation Processes for Environmental Protection; Aquatic Pollution; Aqueous solutions; Atmospheric Protection/Air Quality Control/Air Pollution; Drinking water; Drug Combinations; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Environmental science; equations; indoxacarb; Insecticides; Insecticides - chemistry; Irradiation; Light; Macrolides - chemistry; Oxazines - chemistry; Oxidation; Oxides; Pesticides; Photocatalysis; Photodegradation; Photolysis; Pollutants; Pollution abatement; Semiconductor materials; Semiconductors; spinosad; Studies; Titanium - chemistry; Titanium dioxide; Toxicity; Waste Water Technology; Water - chemistry; Water Management; Water Pollutants, Chemical - chemistry; Water Pollution Control; Water Purification - methods; Water treatment; zinc; Zinc oxide; Zinc oxides; Semiconductor materials; Water detoxification; Insecticides; Zinc oxide; Zinc titanates; Titanium dioxide; Photocatalytic oxidation
• ISSN: 0944-1344; 1614-7499
• DOI: 10.1007/s11356-014-2930-8

The photodegradation of indoxacarb, a broad spectrum foliar insecticide and spinosad, a natural insecticide containing two active ingredients, spinosyn A (major component) and spinosyn D (minor component), was studied in aqueous suspensions of binary (ZnO and TiO₂) and ternary (Zn₂TiO₄ and ZnTiO₃) oxides under artificial light (300–460 nm) irradiation. As expected, the influence of the semiconductor materials on the degradation of both was very significant in all cases. Photocatalytic experiments showed that the addition of semiconductors in tandem with Na₂S₂O₈ as electron acceptor strongly improved the removal of indoxacarb and spinosad in water compared with the photolytic tests. The reaction rates significantly increased, especially for the ZnO/Na₂S₂O₈ and TiO₂/Na₂S₂O₈ systems. The first-order equation (monophasic model) satisfactorily explained the disappearance process, although it offered no explanation for the small concentrations remaining in the process.