Characterization of palmitic and lauric acid aerosols from rapid expansion of supercritical CO2 solutions

Abstract

Palmitic acid aerosols and lauric acid aerosols were generated by rapid expansion of supercritical CO2 solutions. The particle properties were analysed by rapid-scan infrared spectroscopy in situ, by X-ray powder diffraction, with a scanning mobility particle sizer, and by scanning electron microscopy. Particles with irregular elongated shapes were found. Most particles and agglomerates have sizes between 250 and 750 nm. Fewer agglomerates with sizes up to several microns are observed. Our investigation reveals that strong agglomeration takes place at the Mach disc. Palmitic and lauric acid particles are both crystalline and most particles crystallize in the C-form.