Optimization of biodiesel production process from papaya (Carica papaya) seed oil

Optimization of biodiesel production from non-edible Carica papaya seed oil was experimentally investigated in this study. Biodiesel production process parameters such as methanol: oil molar ratio, catalyst type and their concentrations, reaction temperature and reaction time were evaluated. It was found that the optimum process parameters for transesterification of the Carica papaya seed oil at an agitation speed of 600 rpm were: methanol: oil molar ratio 10.0:1; KOH catalyst concentration 1% (of oil weight); reaction temperature of 45°C and reaction time of 60 min. At these reaction conditions, the experimental biodiesel yield was found to be 96.5%. The biodiesel properties were characterized and the results obtained were found to satisfy ASTM D6751 standards. It was therefore concluded that the papaya seed oil biodiesel could be used as an alternative biofuel for diesel engines without any major engine modification.