2,4-D abatement from groundwater samples by photo-Fenton processes at circumneutral pH using naturally iron present. Effect of inorganic ions.
This study evaluated, at laboratory scale, if the using iron naturally present (0.3 mg L-1) and adding 10 mg L-1of hydrogen peroxide was effective to remove 24.3 mgL-1of 2,4-dichlorophenoxyacetic acid (2,4-D) from groundwater samples by simulated solar irradiation (global intensity = 300 W m-2). Under these conditions, the degradation of 2,4-D reached 75.2 % and the apparition of its main oxidation byproduct 2,4-dichlorophenol (DCP) was observed. On the other hand, pH exhibited an increasing from 7.0 to 8.3 during the experiment. Experiments using Milli-Q water at pH 7.0, iron, and H2O2concentrations of 0.3 and 10 mg L-1, respectively, were carried out in order to study the effect of ions such as carbonate species, phosphate, and fluoride in typical concentrations often found in groundwater. Ion concentrations were combined by using a factorial experimental design 23. Results showed that carbonates and fluoride did not produce a detrimental effect on the 2,4-D degradation, while phosphate inhibited the process. In this case, the pH increased also from 7.0 to 7.95 and 8.99. Effect of parameters such as pH, iron concentration, and hydrogen peroxide concentration on the 2,4-D degradation by the photo-Fenton process in groundwater was evaluated by using a factorial experimental design 23. Results showed that the pH was the main parameter affecting the process. This study shows for the first time that using the photo-Fenton process at circumneutral pH and iron naturally present seems to be a promising process to remove pesticides from groundwater.
Environmental Microbiology and Biotechnology Laboratory, Engineering School of Environmental and Natural Resources, Engineering Faculty, Universidad del Valle - Sede Meléndez, A.A. 25360, Calle 13 No. 100-00, Santiago de Cali, Valle, Colombia.
Héctor M
HM
Gutiérrez-Zapata
Environmental Microbiology and Biotechnology Laboratory, Engineering School of Environmental and Natural Resources, Engineering Faculty, Universidad del Valle - Sede Meléndez, A.A. 25360, Calle 13 No. 100-00, Santiago de Cali, Valle, Colombia.
Karen L
KL
Rojas
Environmental Microbiology and Biotechnology Laboratory, Engineering School of Environmental and Natural Resources, Engineering Faculty, Universidad del Valle - Sede Meléndez, A.A. 25360, Calle 13 No. 100-00, Santiago de Cali, Valle, Colombia. janeth.sanabria@correounivalle.edu.co.
Janeth
J
Sanabria
Centro de Investigación y Desarrollo en Ciencias Aplicadas "Dr. J.J. Ronco" (CINDECA), Departamento de Química, Facultad de Ciencias Exactas, UNLP-CCT La Plata, CONICET, 47 No. 257, 1900, La Plata, Buenos Aires, Argentina. julianregifo@quimica.unlp.edu.ar.
Julián Andrés
JA
Rengifo-Herrera
D015084:2,4-Dichlorophenoxyacetic Acid / Q000737:chemistry*; D060587:Groundwater / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000737:chemistry*; D010084:Oxidation-Reduction; D010782:Photolysis; D014874:Water Pollutants, Chemical / Q000737:chemistry*
C045076:Fenton's reagent; D014874:Water Pollutants, Chemical; D015084:2,4-Dichlorophenoxyacetic Acid; D006861:Hydrogen Peroxide; D007501:Iron
2,4-D; Advanced oxidation processes; Circumneutral pH; Fluoride; Groundwater; Photo-Fenton