In this work, the depletion of a commercial formulation of the pesticide glyphosate (RoundUp) using photolysis, electrolysis and photo-electrolysis with diamond anodes was studied. Results show that single photolysis is an inefficient technology for the removal of the pesticide; however, when coupled with electrolysis the removal yield significantly improves. The use of a combined process (photo-electrolysis) leads to the generation of higher concentrations of free radicals from the photo-activation of the oxidants electrogenerated. A major finding is that the supporting electrolyte plays a key role on the removal of glyphosate due to the generation of different oxidant species. Such species (peroxocarbonates, peroxosulfates and hypochlorite) also contribute to the depletion of the pesticide. Furthermore, the removal of glyphosate is clearly influenced by the current density because of the strong relationship between this parameter and the oxidants produced on the anode surface.

This work focuses on the removal of herbicide glyphosate by electrolysis with boron doped diamond anodes. Both the electrolysis of the pure reagent and that of a commercial dispersion (RoundUp) are evaluated. Results show that it is possible to attain a complete mineralization of this herbicide and point out the key role of the supporting electrolyte in the efficiency of the process. This role is explained in terms of the electrogeneration of oxidants. The electrolysis of glyphosate also leads to the release of phosphate and nitrate anions. Further electrochemical and chemical reactivity explains the occurrence of ammonium and other nitrogen species in the electrolyte during the process. Regarding the influence of the type of herbicide (chemical or commercial), competitive reactions have been observed between the electrolysis of herbicide and surfactant, which help to explain the lower efficiency observed in the degradation of RoundUp. Regarding the influence of the operation current density, the process is found to be more efficient at low current densities but at these conditions it is not possible to attain the complete mineralization of pollutant.

This work reports the results of a study in which the remediation of soil that undergoes an accidental discharge of oxyfluorfen is carried out by using electrokinetic soil flushing (EKSF). Two different electrode configurations were tested, consisting of several electrodes surrounding an electrode of different polarity (so-called 1A6C, one anode surrounded by six cathodes, and 1C6A, one cathode surrounded by six cathodes). A pilot plant scale was used (with a soil volume of 175dm(3)) to perform the studies. During the tests, different parameters were measured daily (flowrates, pH, electrical conductivity and herbicide concentration in different sampling positions). Furthermore, at the end of the test, a complete post-mortem analysis was carried out to obtain a 3-D map of the pollution, pH and electrical conductivity in the soil. The results demonstrate that electrode arrangement is a key factor for effective pollutant removal. In fact, the 1A6C configuration improves the removal rate by 41.3% versus the 27.0% obtained by the 1C6A configuration after a period of 35days. Finally, a bench mark comparison of this study of soil remediation polluted with 2,4-D allows for significant conclusions about the scale-up and full-scale application of this technology.

In this work, an accidental spill of Fluoxyl (commercial herbicide containing oxyfluorfen) is simulated in a pilot plant with a soil volume of 70x50x50 cm 3. The transport of Fluoxyl obtained by the free diffusion of pollution and under the application of the electrokinetic fences (EKF) technology are compared in a 34-day treatment. In addition, the temperature, conductivity, and pH are monitored daily. At the end of the experiment, a post-mortem analysis is carried out in order to obtain a 3-D distribution map of the pollutant. The results show that EKF is a good technology to remove oxyfluorfen from the soil without excavation because it is able to attain a fast transfer of oxyfluorfen to the flushing fluid used. After 34 days, the decrease in the concentration of oxyfluofen in the

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