Utilization ultrasonic to increase the efficiency of oil extraction for microalgae indigenous isolates from pond gresik, east java

The prospect of microalgae biomass as biodiesel is a renewable energy to substitute for petroleum. Identification of microalgae indigenous from Gresik ponds, East Java are 29 species, and at Biological laboratory, Science Faculty, UM was able to isolate 10 species. Among the isolated, there are 2 species that faster growth rate, Chlorella vulgaris and Spirogyra sp. Generally, extraction of oil from microalgae biomass requires a long time. The aims from the research are to examine three methods of oil extraction from the two species of microalgae, the experimental laboratory techniques. Biomass of microalgae dry powder was extracted using the solvent n-hexane by three methods, Soxhlet, maceration and ultrasonic waves. On the acquisition of microalgae oil the yield equivalent, compared with extraction time from the three methods. The smaller time of microalgae oil extraction is the more efficient extraction. The results showed: (1) The use of ultrasonic waves can improve the efficiency of microalgae oil extraction. (2) The yield of algae oil which is extracted using the method Soxhlet, maceration, and extraction with the aid of ultrasonic waves in a row is 1.58%, 1.03%, and 1.77% by the time it takes for 18 hours, 8 hours, and 2.33 hours.