Experimental assessment of biobutanol degradation exposed to automotive components: A material compatibility approach

Abstract

This study investigates the corrosive nature of gasoline engine parts such as piston, ring and valve exposed to various biobutanol ratios by static immersion method at different immersion durations. After immersion, variations in the surface morphology and elemental compositions of the metal samples were studied with the help of SEM and XRD results. The degradation in fuel characteristics such as density, viscosity and TAN were investigated as per the ASTM standards. According to the experimental findings, the piston sample is identified as least resistive than other components and resulted in more corrosive oxides. Among the various fuel blends, the degradation of fuel samples and corrosion rate of metals are comparatively higher for pure butanol and lower for gasoline (Bu0 <Bu20 <Bu50 <Bu100). The oxygen content that exists in the biobutanol chemical composition promotes the corrosiveness of the blends. To balance that, the OH functional group of biobutanol acts as a corrosion inhibition factor to restrict aggressive corrosion. Even though Bu100 ended with a higher corrosion rate, it can be used as a standalone fuel in gasoline because the results achieved were within the acceptable limit and has no severe influence on the failure of engine components due to corrosion.