Non-spherical particle formation induced by repulsive hydration forces during spray drying
Source abstract
Abstract
Non-spherical particles were produced during a spray-drying process, but the exact mechanism of their formation was unknown. The non-spherical particles form when the strength of the colloidal droplets is exceeded by external stress stemming from drag in the velocity gradient. Here, we show that repulsive hydration forces reduce the mechanical strength of the droplets; this is critical to the formation of non-spherical particles. Toroidal or ellipsoidal particles were prepared from low-concentration hydrophilic SiO2, TiO2, and CuO colloidal solutions, but not from hydrophobic ZnO colloidal solutions. The surface properties of the solid particulates are crucial for the morphology of particles formed during spray drying.
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Microencapsulation and Drying Processes · Electrohydrodynamics and Fluid Dynamics · Aerosol Filtration and Electrostatic Precipitation
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References (16)
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