A significant issue in the petroleum business is the presence of intricate emulsions, with the primary difficulty being the development of an effective separation approach for complex water-in-oil (W/O) emulsions. The development of a rigid layer at the water-oil interface is the source of W/O emulsion stability. This study examined the separation of water-in-oil emulsions by ultrasonic-assisted demulsification. We employed an ultrasonic water bath apparatus operating at a frequency of 40 kHz with a power output of 180 W. The emulsion was formulated using 45% water and 55% heavy fuel oil by volume. To improve separation performance, silica particles measuring less than 53 μm were employed at a concentration of 1000 ppm. We conducted the ultrasonic treatment for 10 minutes at a temperature of 70°C. The results showed that this method achieved a separation efficiency of 78%, emphasizing the important role of ultrasonic energy and silica nanoparticles in breaking up emulsions and speeding up the merging of water droplets. The results showed that the ultrasonic technique is a promising eco-friendly technology, suggesting it could be a practical and environmentally safe way to separate oil and water. Furthermore, the results showed that a chemical-derived emulsification breaker (silica particle) outperformed a commercial emulsification breaker (RQ35) in terms of separation efficiency.
