Combined process for 2,4-Dichlorophenoxyacetic acid treatment-Coupling of an electrochemical system with a biological treatment

Jean-Marie Fontmorin (1) , Florence Fourcade (1) , Florence Geneste (1) , Didier Floner (1) , Samuel Huguet (1) , Abdeltif Amrane (1)

1 ISCR - Institut des Sciences Chimiques de Rennes

A coupled process was studied for the removal of a chlorinated pesticide: 2,4-Dichlorophenoxyacetic acid (2,4-D). A home-made electrochemical flow cell was used for the pre-treatment and a biological treatment was then carried out using activated sludge supplied by a local wastewater treatment plant. 2,4-D was used as a target compound for the study. Several parameters were monitored during the biological treatment, like dissolved organic carbon (DOC), the target compound and the major by-product. Pretreatment led to a quick decrease of DOC during the biological process, since a 66% mineralization yield was measured after the second day, and 79% after the seventh day of culture. After two days of treatment, HPLC results revealed a total degradation of Chlorohydroquinone, the major by-product. The electrochemical pretreatment shortened the length of the biological treatment, since DOC measurements showed that in the case of non-pretreated 2,4-D, no mineralization was observed before day 7. These promising results should be subsequently confirmed on commercial 2,4-D-containing solutions and then on real effluents.

Mots clés: SEQUENCING BATCH REACTORS; WASTE-WATER; PHOTOCATALYTIC DEGRADATION; 4-D METABOLISM; MINERALIZATION; OXIDATION; HERBICIDES; BIODEGRADATION; PESTICIDES; OZONATION

Domaines: Biochimie [q-bio.BM]

Jean-Marie Fontmorin, Florence Fourcade, Florence Geneste, Didier Floner, Samuel Huguet, et al.. Combined process for 2,4-Dichlorophenoxyacetic acid treatment-Coupling of an electrochemical system with a biological treatment. Biochemical Engineering Journal, 2013, 70, pp.17-22. ⟨10.1016/j.bej.2012.09.015⟩. ⟨hal-00805125⟩