Optimization of pongamia methyl ester from transesterification process and fuel characterization as a diesel substitute

In the present study non-edible tree born pongamia seed oil is subjected to esterification followed by transesterification with methanol in presence of potassium hydroxide as catalyst for fuel characterization. The effect of process parameters such as molar ratio, preheating temperature, catalyst concentration and reaction time was studied to standardize the transesterification process for estimating the highest recovery of ester with lowest possible viscosity. Based on the observations of the ester recovery and kinematic viscosity, it was found that filtered pongamia oil at 6:1 molar ratio (methanol to oil) preheated at 70°C and maintaining 60°C reaction temperature for 75 min in the presence of 1.5% KOH and then allowed to settle for 24 hrs resulted in lowest kinematic viscosity (5.93cSt) with highest ester recovery (95%). Different properties of pongamia oil and its methyl ester like density, viscosity, pour and cloud point, calorific value, flash and pour point were determined. Results show that the methyl ester of pongamia is an excellent substitute for fossil fuels.