Supercritical Assisted Electrospray: An Improved Micronization Process.

Area of Science:

• Chemical Engineering
• Materials Science
• Particle Technology

Background:

• Classical electrospray (ESPR) atomization faces limitations in efficiency and particle size control.
• High molecular weight polymers present challenges for traditional particle generation methods.

Purpose of the Study:

• To introduce and evaluate a new electrospray process incorporating supercritical CO₂ (SC-CO₂) for improved particle generation.
• To investigate the effect of SC-CO₂ on liquid properties and particle characteristics.
• To optimize particle size and production rate for polyvinylpyrrolidone (PVP) using the novel method.

Main Methods:

• Dissolving polyvinylpyrrolidone (PVP) in a liquid mixture.
• Introducing supercritical CO₂ (SC-CO₂) to form an expanded liquid for electrospray.
• Testing the process at varying PVP concentrations (1-5% w/w) and pressures (80-120 bar).
• Analyzing particle size distribution and production rates.

Main Results:

• The addition of SC-CO₂ significantly reduced surface tension and viscosity of the polymer solution.
• The process enabled the production of micro/nanoparticles with controlled size and distribution.
• Achieved repeatable microparticle diameters ranging from 0.55 to 2.25 µm.
• Production rates were up to 100 times higher compared to traditional ESPR.

Conclusions:

• The SC-CO₂ enhanced electrospray process offers a significant improvement over classical ESPR for particle generation.
• This method is effective for producing controlled micro/nanoparticles from high molecular weight polymers like PVP.
• The process demonstrates potential for high-throughput, efficient particle manufacturing with tunable characteristics.