Performance of sonication and microfluidization for liquid-liquid emulsification

Area of Science:

• Chemical Engineering
• Materials Science

Background:

• Liquid-liquid emulsions are crucial in various industrial applications, including microencapsulation.
• Efficient preparation methods are needed to control emulsion properties like droplet size.

Purpose of the Study:

• To compare the efficacy of sonication and microfluidization in preparing water-in-oil and oil-in-water emulsions.
• To characterize emulsion droplet size and evaluate the influence of viscosity on emulsification.

Main Methods:

• Emulsification was performed using a benchtop sonicator and an air-driven microfluidizer.
• Droplet size of the liquid-liquid emulsions was measured using a laser-based particle size analyzer.
• The effect of dispersion and dispersed phase viscosity on emulsification was investigated.

Main Results:

• Microfluidization demonstrated excellent emulsification efficiency, particularly for more viscous solutions.
• Sonication's efficiency was influenced by viscosity, with increased dispersion phase viscosity improving results, but increased dispersed phase viscosity hindering them.
• Sonication generated more heat compared to microfluidization, posing a risk for heat-sensitive materials.

Conclusions:

• Microfluidization is a highly effective method for liquid-liquid emulsification, especially for viscous systems.
• Sonication can be comparable to homogenization but is less effective for highly viscous solutions and generates more heat.
• The findings provide a basis for selecting large-scale emulsification techniques in microencapsulation processes.