Response Surface Methodology (RSM) was applied based on central composite rotatable design (CCRD) to optimize transesterification reaction parameters for obtaining optimal biodiesel yield from Jatropha curcas oil. Transesterification variables such as: catalyst concentration (CC) (0.16-2%), reaction temperature (RT) (40-65°C), molar ratio of oil and methanol (0.95-11.5), and reaction time (30-140 min) were optimized via RSM involving 24 full factorial CCRD design. The molar ratio of methanol to oil and RT were the most significant (p< 0.5) factors affecting the yield of Jatropha curcas oil methyl esters (JOMEs). A linear relationship was recorded between the observed and predicted values (R2 = 0.766). Using multiple regression analysis, a quadratic polynomial equation was constructed to predict JOMEs yield. The quadratic term of molar ratio showed a significant impact on the JOMEs yield. The interaction terms of molar ratio and CC with reaction time exhibited positive impact on ester yield (p< 0.05). The optimum reaction conditions including CH3OH to oil ratio of 6:1, 1.0 % CC, 60 °C RT and 60 min reaction time offered the highest yield of JOMEs (99.90%). JOMEs were analytically characterized using GLC and FTIR. The fuel properties of produced JOMEs were in accordance to ASTM D6751 and EN 14214 standards.


Tahir Mehmood, Adeela Naseem, Farooq Anwar, Mudassir Iqbal and Muhammad Ashraf Shaheen