VATIS UPDATE Article

Researchers from Kumamoto University, Japan, have used a nanosecond pulsed electric field to extract hydrocarbons from microalgae. By using the shorter duration pulse, they were able to extract a large amount of hydrocarbons from the microalgae in a shorter amount of time, using less energy, and in a more efficient manner than current methods. Researchers used a nanosecond PEF (nsPEF) to focus on the microalgae matrix instead of the cells.

The researchers performed several tests with the nsPEF on the microalgae Botryococcus braunii (Bb) to determine the optimal electric field, energy, and pulse repetition frequency for hydrocarbon extraction. Interestingly, it was found that doubling the energy only resulted in a 10% increase in hydrocarbon extraction. At 10 Hz, the optimal field and energy conditions were determined to be approximately 50 kV/cm and 55.6 J/ml respectively per volume of algae.

Further, the researchers found that pulse frequency had little to no effect on extraction percentage, meaning that a large amount of hydrocarbons may be extracted quickly for large/industrial systems. “Other microalgae do not secrete a matrix so the cell membranes must be damaged or destroyed to get at the hydrocarbons, which both takes more energy and is less efficient than our method,” said Hamid Hosseini, at Kumamoto University.