An Experimental Study on Microalgae Oil Extraction Through Ultrasound-assisted Algasonic Machine

¹ Department of Food Science and Biotechnology, Faculty of Agricultural Technology, Universitas Brawijaya, Malang, East Java, Indonesia
² Department of Agricultural and Biosystem Engineering, Faculty of Agricultural Technology, Universitas Brawijaya, Malang, East Java, Indonesia

^* Corresponding author: endrika_w@ub.ac.id

Abstract

The rise in fuel consumption has led to a renewable energy crisis, highlighting the importance of finding alternatives to fossil fuels, such as biodiesel. Microalgae, recognized as a promising oil source, plays a pivotal role in third-generation biodiesel. However, efficient, eco-friendly methods are needed to extract oil from microalgae. Among the various techniques, the ultrasound method has shown notable effectiveness in disrupting microalgae cell walls, enabling oil release. Despite its success, its high cost remains a significant challenge. To address this issue, an innovative microalgae oil-extraction machine was developed. The machine incorporates a 40 kHz ultrasound transducer, heater, and automatic control panel. Tests indicated an energy consumption cost of approximately Rp 1,000.00 per process. Using this system, oil yields were achieved at 19.25% oil yield from Chlorella vulgaris with a 3.24% Free Fatty Acid (FFA) level, making it suitable for biodiesel. Similarly, Nannochloropsis oculata yielded 23.07% oil with a 1.79% FFA level, also suitable for biodiesel. Overall, the Nannochloropsis oculata strain demonstrated the highest potential for biodiesel production, with optimal extraction occurring within 180 minutes. This research highlights the potential of ultrasound technology in microalgae oil extraction for biodiesel, offering a cost-effective and a sustainable approach to addressing the energy crisis.