AGEING EFFECTS OF KARANJA BIODIESEL WHEN TREATED WITH VARIOUS ANTIOXIDANTS

This study investigates the impact of various synthetic phenolic antioxidants on the oxidation stability of biodiesel blends with the employment of the modified Rancimat method. The experimental results revealed that an improvement in oxidation stability could be achieved with all antioxidants tested. Propyl Gallate (PG) displayed the strongest effectiveness in neat biodiesel, whereas their use in biodiesel blends showed a greater stabilizing potential. During a naturally ageing process of the biodiesel blends which was conducted for a period of 06 weeks, samples were taken every week to measure the induction period, peroxide value, , iodine value, acid value, calorific value and kinematic viscosity properties. This process was designed in such manner to simulate the ageing of an automotive biofuel stored in the fuel tank of a vehicle. The results showed a sharp decrease in fuel stability over time. Although limited effects were observed in viscosity, the acid value was significantly increased over time. The addition of antioxidants resulted in some increases in viscosity and acid value of the biodiesel blends