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’ time interval term as long-term stability reported as a fraction of phase separation in percentage (f (%)). 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.