Photo-Fenton degradation of a herbicide (2,4-D) in groundwater for conditions of natural pH and presence of inorganic anions.
J Hazard Mater
; 372: 113-120, 2019 06 15.
Article
em En
| MEDLINE
| ID: mdl-29678309
The effects of four inorganic anions (Cl-, SO42-, HCO3-, NO3-) usually present in groundwater were investigated on the photo-Fenton degradation of 2,4-dichlorophenoxyacetic acid (2,4-D). A kinetic model derived from a reaction sequence is proposed using the ferrioxalate complex as iron source at pH close to natural conditions (pHâ¯=â¯5). It was demonstrated that oxalate not only maintained iron in solution for the natural groundwater system, but also increased the photochemical activation of the process. Results showed that the minimum conversion of 2,4-D for the simulated groundwater after 180â¯min was 63.80%. This value was only 14.1% lower than the conversion achieved without anions. However, with all anions together, the consumption of hydrogen peroxide (HP) per mole of herbicide showed an increase with respect to the test without anions. Only one kinetic parameter was estimated for each anion applying a nonlinear regression method. Subsequently, these optimized kinetic constants were used to simulate the system behaviour, considering the influence of all the studied anions together. A good agreement between kinetic model predictions and experimental data was observed, with the following errors: RMSE2,4-Dâ¯=â¯3.98â¯×â¯10-3 mM, RMSEHPâ¯=â¯1.83â¯×â¯10-1â¯mM, RMSEOXâ¯=â¯1.39â¯×â¯10-2â¯mM, and RMSE2,4-DCPâ¯=â¯5.59â¯×â¯10-3⯠mM.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
J Hazard Mater
Assunto da revista:
SAUDE AMBIENTAL
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Argentina
País de publicação:
Holanda