Advanced oxidation of commercial herbicides mixture: experimental design and phytotoxicity evaluation

CRISTINA ZALAZAR; ALEJANDRO LOPEZ; MAIA LESCANO; ANDREA COLL

ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH

SPRINGER HEIDELBERG

Lugar: HEIDELBERG; Año: 2018 vol. 25 p. 21393 - 21402

0944-1344

In this work, the suitability of the UV/H2O2process for commercial herbicides mixture degradation was studied. Glyphosate,the herbicide most widely used in the world, was mixed with other herbicidesthat have residual activity as 2,4-D and atrazine. Modeling of the processresponse related to specific operating conditions like initial pH and initial H2O2to Total Organic Carbon molar ratio was assessed by the response surfacemethodology (RSM).Results have shown that second-order polynomial regression model couldwell describe and predict the system behavior within the tested experimentalregion. It also correctly explained the variability in the experimental data. Experimentalvalues were in good agreement with the modeled ones confirming the significanceof the model and highlighting the success of RSM for UV/H2O2process modeling.Phytotoxicity evolution throughout the photolytic degradation processwas checked through germination tests indicating that the phytotoxicity of theherbicides mixture was significantly reduced after the treatment. End point forthe treatment at the operating conditions for maximum TOC conversion was alsoidentified.