Effect of corrosion inhibitors on corrosiveness of palm biodiesel

The present study aims to investigate the effect of two organic corrosion inhibitors, i.e. benzotriazole and adenine on the corrosion behaviour of copper and mild steel upon exposure to palm biodiesel. Static immersion tests were conducted by exposing copper and mild steel coupons to palm biodiesel (B100) in the presence and absence of two different corrosion inhibitors at room temperature (25-27 degrees C) for 60 days. Benzotriazole and adenine were added to palm biodiesel at 100, 200, 300 ppm concentrations. In molarity, these concentrations will be 0.72, 1.44, 2.16 mol L-1 and 0.64, 1.27, 1.90 mol L-1 for benzotriazole and adenine respectively. Exposed metal surfaces were characterised by SEM, EDS and atomic force microscopy analysis. Results showed that mild steel surface has degraded comparatively less than that of copper surface in palm biodiesel without corrosion inhibitors. However, benzotriazole was found to be more effective in corrosion inhibition of copper and mild steel than that of adenine in palm biodiesel.