Corrosion Rate of API 5L-X52 Steel for the Biofuels Transportation

The alternative use of ethanol as a biofuel, or total or partial substitute for fossil fuels, has a significant effect when blend with ethanol-gasoline, this addition of gasoline increases the octane number and reduces CO2 emissions from cars. In this study, water concentrations (0.5 and 5%) were used in 10, 85 and 95% (% V) ethanol blends, using the electrochemical linear polarization resistance (LPR) technique in steel pipe API-5L X52. As complementary techniques, pH and conductivity were monitored before and after each test. The objective of this research is to measure the effect of water on the corrosion rate of the ethanol blends. As a result, it was obtained that the solutions with higher water concentration had the highest value of corrosion rate, as well as localized corrosion damage in both cases, which was corroborated by scanning electron microscopy (SEM).