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

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

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 groundwaterconditions is presented. A kinetic model derived from a reactionsequence is proposed to study the influence of the commonlyanions (Cl-, SO4-2, HCO3- and NO3-) present in this type of watersusing the ferrioxalate complex as iron source and conditions of pHclose to neutrality. Applying a nonlinear regression procedure, agood correlation was obtained between the experimental data andthe results obtained with the model. The errors (RMSE) obtainedwere 4.48 ×10-3 mM, 3.29 ×10-3 mM, 2.54 ×10-3 mM and 4.72 ×10-3mM for 2,4-D, Cl-, SO4-2, HCO3- and NO3-, respectively. It wasfound that the photo-Fenton process is effective in the degradationof the herbicide employing a groundwater matrix when ferrioxalateis used as the catalyst source. A reduction of only 14.3 % in theconversion of 2,4-D after 180 min of reaction was observed whenevaluating the system with the mixture of all the anions.