The present work investigates the use of W/WO3 electrodes prepared by electrochemical anodization applied in the photoelectrocatalytic disinfection of Candida parapsilosis using ultraviolet-visible (UV-Vis) and visible irradiation. The core objective of this work lies in describing a novel approach involving the use of chloride as supporting electrolyte, aiming at achieving a faster inactivation and towards understanding its behavior in water containing high chloride content. The best experimental conditions were found to be at pH 7.0 and 0.1 mol L-1 NaCl when the photoelectrode was biased at 1.5 V (vs. Ag/AgCl) illuminated by both UV-Vis and visible light. It is suggested that charges photogenerated on the electrode surface give rise preferably to HO•, known to be powerful oxidant that causes the total inactivation of the microorganism (1 min of treatment) while engendering around 84% of mineralization of organic matter released from the cell damage following 120 min of treatment.

We have studied the treatment of Reactive Black 5 (RP5) and Blue 19 (RA19), which are respectively azo and anthraquinone textile dyes, by electrochemical oxidation using a non commercial boron doped diamond electrode supported on titanium metallic with a relation between B and C equal to 15,000 ppm. Pt was used as counter electrode and Ag/AgCl(sat) was the reference electrode. The variables investigated to optimize the degradation were support electrolyte concentration (0.05, 0.1 and 0.2 mol L-1 of K2SO4), temperature (25, 35 and 45 ºC) and pH (2.5 and 10) by applying a current density of 75 mA cm-2. Total decolorization was observed in all electrochemical conditions studied. The highest rates of mineralization and chromatographic area removal were attained at high support electrolyte concentration due to the increase of conductivity, which caused more generation of hydroxyl radicals. RP5 was degraded at lower electrolysis time than RA19 with smaller requirement of electric charge. The mineralization rate increased in acid medium and at higher temperature since the increase in temperature favors the generation reactions of persulfate. These conditions led to the highest levels of current efficiencies and lower energy consumed.