A. Frías-Ferrer

Electrochemical degradation of perchloroethylene in aqueous media: an approach to different strategies.

An approaching study to the electrochemical degradation of perchloroethylene (PCE) in water has been carried out using controlled current density degradation electrolyses. The different electrochemical strategies to degrade perchloroethylene in aqueous media (i.e. cathodic, anodic and dual treatments) have been checked using divided and undivided configurations. The influence of the initial concentration, pH and current density on the general behavior of the system has been studied, and special attention was paid to the nature of the byproducts formed and to the analysis of the closed mass balance at the end of the reaction. Results from several analytical techniques have been compared. Undivided configuration provides the best results in these experimental conditions, with degradation percentages higher than 50% and with only 6% of the initial perchloroethylene concentration remaining in the system.

Lead dioxide film sonoelectrodeposition in acidic media: Preparation and performance of stable practical anodes.

Practical lead dioxide anodes have been obtained by electrodeposition on glassy carbon and titanium substrates in the presence and in the absence of an ultrasound field. The films obtained by mechanical agitation on glassy carbon are strongly improved when the electrodeposition process is carried out with the ultrasound field, providing adherent deposits free from nodules and stress, but with pores appearing occasionally. These enhanced properties were not achieved by mechanical conditions, even when optimization of temperature, current density, additives and geometrical aspects was attempted. The best practical anodes were obtained by sonoelectrodeposition using specially treated titanium as substrate, providing comparable behavior to commercial electrodes.