Biodiesel from Fried Oil Using Microwaves, Ultrasounds and Heterogeneous Catalysis

E. Viola, V. Valerio & F. Zimbardi
To evaluate the efficiency of the transesterification of fried oils by using heterogeneous catalysis, three different systems have been compared: 1) flask in hot bath with magnetic stirrer; 2) flask in microwave oven with a stirring arm; 3) flask in ultrasound bath with a stirring arm. The CaO and SrO were used as heterogeneous catalysts. The transesterification has been carried out at 65 °C, using methanol/oil ratio 12:1 and catalyst load of 0.7%. The efficiency...