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

LÓPEZ, ALEJANDRO; COLL, ANDREA; LESCANO, MAIA; ZALAZAR, CRISTINA

ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH

SPRINGER HEIDELBERG

Lugar: HEIDELBERG; Año: 2018

0944-1344

In this work, the suitability of the UV/H2O2 processfor commercial herbicides mixture degradation was studied.Glyphosate, the herbicide most widely used in the world, wasmixed with other herbicides that have residual activity as 2,4-D and atrazine. Modeling of the process response related tospecific operating conditions like initial pH and initial H2O2 tototal organic carbon molar ratio was assessed by the responsesurface methodology (RSM). Results have shown thatsecond-order polynomial regression model could well describeand predict the system behavior within the tested experimentalregion. It also correctly explained the variability inthe experimental data. Experimental values were in goodagreement with the modeled ones confirming the significanceof the model and highlighting the success of RSM for UV/H2O2 process modeling. Phytotoxicity evolution throughoutthe photolytic degradation process was checked through germinationtests indicating that the phytotoxicity of the herbicidesmixture was significantly reduced after the treatment.The end point for the treatment at the operating conditionsfor maximum TOC conversion was also identified.