Simultaneous extraction of rapeseed oil and conversion to biodiesel using heterogeneous and homogeneous catalysts

In this study, first rapeseed oil was extracted by different ratio of Methanol/n‐Hexane mixture as solvent during 8 h in a Soxhlet extractor. During all experiments the other parameters such as amount of solvent (250 cc) and rapeseed (45 g), stirrer speed (750 rpm) and temperature (80°C) were kept constant. The maximum yield of oil (45.33%) was obtained by 50/50% (Methanol/n‐Hexane) volumetric ratio. Later, the extraction and trans‐esterification were carried out simultaneously employing each of the two selected alkali catalysts. The results showed that applying of 11% (wt%) CaO for 8 h, produced the ultra‐pure biodiesel of 99.92% having yield of 80.49% whereas using 2% KOH for 4 h, resulted 95.74% purity with the yield of 87.23%. © 2017 American Institute of Chemical Engineers Environ Prog, 37: 518–523, 2018