Production of Biodiesel from a Blend of Jatropha Oil and Waste Frying Soybean Oil

Biodiesel was produced from various blends of jatropha oil and waste frying soybean oil (WFSO). The process used was two-step transesterification, as free fatty acid (FFA) content of jatropha oil was high. Esterification was done for 2 h. After esterification the FFA content was reduced to <1%. WFSO having FFA 1.6% was used directly. Transesterification of blends were carried out for 90 min at 55°C, using KOH catalyst and methanol alcohol. The biodiesel produced was settled overnight and separated. It was observed that more amount of catalyst was consumed as the volume percent of jatropha oil in the blend increases. Fuel properties of the biodiesel products have been measured and found markedly enhanced compared to those of the parent oil. Also, the values satisfied the standard limits according to the American Society for Testing and Materials (ASTM).