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Una de las más grandes preocupaciones de la sociedad actual es la calidad del agua en sus diferentes formas (aguas residuales, agua potable, cuerpos de agua), junto con el tratamiento que se les debería de dar. Pero algo poco tomado en cuenta es la presencia de contaminantes emergentes farmacéuticos en cuerpos de agua, más específicamente antibióticos, lo cuales pueden llevar a impactos ambientales negativos graves, desde provocar enfermedades no curables en fauna, hasta poder tener los mismos efectos en la salud humana. Para evitar esto se presenta el proceso electroquímico de Oxidación Electroquímica o Electrooxidación (EO) el cual, según múltiples estudios, puede degradar hasta en un 100% este tipo de fármacos, en aguas residuales, disminuyendo su concentración aguas abajo. 787 / 5000 Resultados de traducción One of the greatest concerns of today's society is the quality of water in its different forms (wastewater, drinking water, bodies of water), along with the treatment that should be given to them. But something little taken into account is the presence of emerging pharmaceutical pollutants in water bodies, more specifically antibiotics, which can lead to serious negative environmental impacts, from causing non-curable diseases in fauna, to being able to have the same effects on human health. To avoid this, the electrochemical process of Electrochemical Oxidation or Electrooxidation (EO) is presented, which, according to multiple studies, can degrade this type of drug by up to 100% in wastewater, reducing its concentration downstream. Ingeniero Ambiental http://unidadinvestigacion.usta.edu.co Pregrado

[ES]: En este trabajo se describe la oxidación anódico de electrodos de plata y de cobre en medios básicos. Se han utilizado tanto medios acuosos como hidróxidos fundidos (eutéctico NaOH/KOH). Los procesos de oxidación se han estudiado mediante voltametría cíclica y cronoamperometría, y las fases resultantes han sido caracterizadas por difracción de Rayos X. Los rangos de estabilidad encontrados para cada uno dependen del medio utilizado. Además de óxidos conocidos de cobre y de plata, se ha aislado un nuevo óxido de plata., [EN]: The anodic oxidations of copper and silver electrodes in basic media are reported. Experiments were conducted both in aqueous NaOH solutions and in a flux of molten NaOH/KOH eutectic. The oxidation processes were studied by means of cyclic voltammetry and chronoamperometries and the phases obtained were systematically characterized by x-ray diffraction. The ranges of stability of each phase in the different media studied are reported. In addition to known oxides of copper or silver, a new silver oxide was isolated., This work was funded by the MCyT(Spain), Plan Nacional de Materiales (MAT2001-1709-C04-01 and MAT2002-04529-C03, MAT96- 1057-c02-01and PGC PB98-0491). We also thank the Ministry of Education and Culture (Spain) for a predoctoral fellowship awarded to EMT-R.

Due to their relatively low price, high surface area and versatile physic-chemical properties, conductive carbon materials are considered among the most promising supports of electroactive species and/or catalysts for different electrochemical devices, like supercapacitors, fuel cells, batteries, sensors, etc. [1]. However, in these applications, carbon supports are usually subjected to oxidation and/or corrosion processes, which can be promoted by the supported electroactive species and/or catalysts [2]. In this sense, although the surface functionalities of carbons seem to play a key role on their electrochemical response and stability, their influence in the presence of electroactive catalysts is still controversial. Particularly, the effect of phosphorous groups has been never reported. In this work, the influence of different oxygen and phosphorous functionalities on the electrochemical behavior of Pt- and Pd-supported activated carbons (ACs) has been studied. Various ACs showing similar surface areas (ca. 1400-1500 m2/g) and a rich variety of surface chemistry, with oxygen and phosphorous-like surface groups, were obtained by physical (CO2) (HAG800 support) or chemical (H3PO4) (HA3500 support) activation of olive stone. The ACs were used as support of Pd, Pt and Pd/Pt catalysts (Fig 1a), with nominal loadings of 0.5-1.0 wt%, by using the incipient-wetting impregnation method. The samples were characterized by N2 and CO2 adsorption, TEM, XRD, XPS, TPD experiments and different electrochemical techniques. Although the supported metals promote carbon electroxidation and/or corrosion (see the higher oxidation currents for the metalloaded sample – Fig 1b), the presence of surface phosphorous groups (HA3500-M samples) results in lower oxidation currents than in the case of P-free samples (HAG800-M samples) (Fig. 1.b). These results are in agreement with the oxidation resistance induced by phosphorous groups in oxidizing gas phase at high temperatures [3], and may support the statement that these phosphorous groups could enhance the durability of carbon-supported metal electrocatalysts for different electrochemical applications. Universidad de Málaga. Campus de Excelencia Andalucía Tech.