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RESUMEN. En este trabajo se determinó del comportamiento a la corrosión del aluminio en diferentes tipos de bioetanoles mezclados con gasolina, los bioetanoles utilizados fueron de manzana, mango, naranja y caña. Las técnicas electroquímicas realizadas fueron espectroscopia de impedancia electroquímica, ruido electroquímico y resistencia a la polarización lineal. Las probetas estuvieron inmersas durante noventa días en las mezclas gasolina con bioetanol en concentraciones de 10 y 20% (en vol.) (E10-E20). Las probetas corroídas fueron analizadas por microscopia electrónica de barrido. Los resultados obtenidos muestran que para las mezclas de bioetanol de naranja, manzana y mango en sus dos concentraciones existe una disminución en sus valores de impedancia con respecto al de la gasolina, siendo el bioetanol de caña el que presenta una susceptibilidad más alta a la corrosión ya que sus valores de impedancia disminuyen hasta cuatro órdenes de magnitud con referencia a la de gasolina. Para la técnica de resistencia a la polarización lineal el bioetanol de mango fue la que presento valores similares al de la gasolina durante los noventa días de inmersión. Para la técnica de ruido electroquímico se obtuvo que tanto para gasolina como para las concentraciones E10 se presentan eventos aislados con una amplitud por encima de la media indicando la existencia de corrosión localizada y para las concentraciones de E20 se presentan transitorios muy discretos con amplitudes característicos de corrosión uniforme o pasivación. Mediante SEM se observó la existencia de corrosión localidad para las probetas en concentración E10 y corrosión uniforme para las probetas en concentraciones E20. ABSTRACT In this work, the corrosion behavior of aluminum in different types of bioethanol/gasoline blends has been evaluated by using electrochemical techniques. Evaluated bioethanols included bioethanol from Apple, mango, orange and sugar cane in concentrations of 10 and 20%, whereas employed techniques included electrochemical impedance spectroscopy (EIS), electrochemical noise (EN) and linear polarization resistance (LPR) during 90 days. Corroded samples were analyzed in a scanning electronic microscope (SEM). Obtained results have shown that orange, apple and mango bioethanols/gasoline, in both concentrations, there is a decrease in the impedance value as compared to that for pure gasoline, with the highest corrosion rate exhibited by the sugar cane bioethanol. LPR results indicate that the mango bioethanol/gasolina blends exhibited similar corrosion rates to that exhibited by gasoline. On the other hand, EN measurements showed that in both pure gasoline and the 10% concentration noise reading showed indicating a high susceptibility towards localized type of corrosion, whereas those exhibited by th 20% concentration indicated a susceptibility towards uniform type of corrosion or passivation, which was corroborated by the SEM micrographs.

In this work, the corrosion behavior of aluminum in different types of bioethanol/gasoline blends has been evaluated by using electrochemical techniques. Evaluated bioethanols included bioethanol from Apple, mango, orange and sugar cane in concentrations of 10 and 20%, whereas employed techniques included electrochemical impedance spectroscopy (EIS), electrochemical noise (EN) and linear polarization resistance (LPR) during 90 days. Corroded samples were analyzed in a scanning electronic microscope (SEM). Obtained results have shown that orange, apple and mango bioethanols/gasoline, in both concentrations, there is a decrease in the impedance value as compared to that for pure gasoline, with the highest corrosion rate exhibited by the sugar cane bioethanol. LPR results indicate that the mango bioethanol/gasolina blends exhibited similar corrosion rates to that exhibited by gasoline. On the other hand, EN measurements showed that in both pure gasoline and the 10% concentration noise reading showed indicating a high susceptibility towards localized type of corrosion, whereas those exhibited by th 20% concentration indicated a susceptibility towards uniform type of corrosion or passivation, which was corroborated by the SEM micrographs.