Investigating the Effect of Cashew Nut Oil (Anacardium occidentale) Biodiesel on Corrosion of Metals

The transition from fossil fuel to clean and renewable fuel is a burning issue in the global space as at present. In addition to other source of energy, renewable liquid fuels such as biodiesel are providing solution to this surging global need. Just like fossil fuels, these renewable fuels come with their own challenges of which corrosion is prime. In this study the corrosion behaviour of metals in cashew nut oil biodiesel was conducted. Oil extracted from Cashew nuts was characterized for acid value free fatty acid and fatty acid profile. The oil was further trans esterified into biodiesel and fuel properties were characterized. Corrosion test for selected metals in biodiesel using mass loss method was also conducted. The acid value and free fatty acid for the oil was observed to be 5.61 mg/g KOH and 2.26 mg/g KOH respectively. The fatty acid profile was observed to be more of monounsaturated fatty acid especially Oleic acid (68.2 wt %) for biodiesel. The corrosion test showed copper metals and mild steel have higher corrosion rate of 0.02896 mm/y and 0.02617 mm/y respectively. Hence the corrosion pattern of metal in cashew nut oil biodiesel is slightly higher than other edible oil biodiesel.