Photo-Fenton degradation of the herbicide 2,4-D for conditions of natural pH and presence of inorganic anions.

CONTE, LEANDRO O.; SCHENONE, AGUSTINA V.; GIMÉNEZ, BÁRBARA N.; ALFANO, ORLANDO M.

Guatapé

Congreso; 3rd Iberoamerican Conference on Advanced Oxidation Technologies (III CIPOA); 2017

The photo-Fenton degradation of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) for naturally groundwater conditions is presented. A kinetic model derived from a reaction sequence is proposed to study the influence of the commonly anions (Cl-, SO4-2, HCO3- and NO3-) present in this type of waters using the ferrioxalate complex as iron source and conditions of pH close to neutrality. Applying a nonlinear regression procedure, a good correlation was obtained between the experimental data and the results obtained with the model. The errors (RMSE) obtained were 4.48 ×10-3 mM, 3.29 ×10-3 mM, 2.54 ×10-3 mM and 4.72 ×10-3 mM for 2,4-D, Cl-, SO4-2, HCO3- and NO3-, respectively. It was found that the photo-Fenton process is effective in the degradation of the herbicide employing a groundwater matrix when ferrioxalate is used as the catalyst source. A reduction of only 14.3 % in the conversion of 2,4-D after 180 min of reaction was observed when evaluating the system with the mixture of all the anions.