Investigation of Metals and Antioxidants on Stability Characteristics of Biodiesel

With rapid rise in global economy, energy demands are rising at a very high rate which has resulted in excessive utilisation of fossil fuel resources. To cope with the energy demand, there is significant research being done in field of alternative fuel resources. Biodiesel offers a great choice being its renewable nature. Biodiesel is mainly derived from vegetable oils like edible, non-edible oils, animal fats and algae. There are various problems associated with use of biodiesel like high viscosity and stability which are long chain fatty acid alkyl esters, which contains unsaturated portions that are susceptible to oxidation. Metal containers used for storage of biodiesel also affects its stability. Antioxidants are often used to inhibit biodiesel oxidative degradation. The present paper investigates the previous research done on effect of metal on stability of biodiesel and there remedial efforts with use of antioxidants. Metals have catalytic effect on biodiesel stability. Pyrogallol is found to be the most effective antioxidant to improve the oxidation stability in case of almost all biodiesels reviewed.