Ultrasound assisted citronella oil in water nanoemulsion and comparison with conventional methods

Abstract

This study involved the acoustic cavitation aided process intensification of citronella oil-based nanoemulsion with varying process parameters. A citronella oil (10 wt. %) in water emulsion was prepared at optimized parameters such as sonication time of 20 min, surfactant concentration of 7.5 wt. % of the total emulsion with (Hydrophilic-lipophilic balance) HLB value of 12 and power amplitude of 35% (of the total power of 750 W). The prepared emulsions stability was assessed over visual observation and kinetic stability of the emulsion after formulation with 7, 30 and 90 days&rsquo; time interval term as long-term stability reported as a fraction of phase separation in percentage (<em>f</em> (%)). The ultrasonically prepared emulsion was found to more stable with the mean droplet diameter (MDD) of 22-23 nm, whereas, conventionally prepared emulsion get separated and creamed within the day as well as formulation required more process time and energy dissipation.