Degradation of the herbicide paraquat by photo-fenton process: optimization by experimental design and toxicity assessment

Journal of the Brazilian Chemical Society

Machado, Antonio E. H.¹  Gomes Junior, Oswaldo¹  Trovó, Alam G.¹  Borges Neto, Waldomiro¹  Departamento Municipal de Água e Esgoto de Uberlândia (DMAE), Uberlândia, Brazil¹  Silva, Jader O.¹  Universidade Federal de Uberlândia (UFU), Uberlândia, Brazil¹ 

关键词: pesticides;    detoxification;    pilot plant;    wastewater treatment;    solar light intensity;   

DOI  :  10.1590/S0103-50532013000100011

学科分类：化学（综合）

来源: SciELO

【 摘 要 】

This study describes the influence and optimization of Fenton's reagent (concentration of Fe2+ and H2O2 ) on the efficiency of mineralization of the herbicide paraquat (PQT, 50 mg L-1) in water, after 60 min (equivalent to 642 kJ L–1 of accumulated UVA radiation) treatment by photo-Fenton process in laboratory scale, using central composite design (CCD). Under optimized conditions, kinetic experiments were done, evaluating the PQT removal, its mineralization and toxicity in laboratory scale, using artificial irradiation, and in a pilot plant under solar irradiation. The same removal efficiency and mineralization of PQT were obtained in both reactors. The toxicity of the samples, estimated in terms of mortality of Artemia salina, decreases simultaneously with the decay of concentration of PQT, suggesting the formation of intermediates of lower toxicity. In this way, the solar photo-Fenton process can be considered as a viable alternative for the treatment of wastewater containing PQT.

【 授权许可】

Unknown