Dissolution kinetics of zinc oxide and its relationship with physicochemical characteristics

Dissolution kinetics of zinc oxide (ZnO) powders used as feed additives for supplementation in diet animals is studied relation to the powder physicochemical characteristics. The fundamental issue discrimination reaction-limited or diffusion-limited dissolution into a stirred liquid medium addressed. Relationships between and properties are investigated set 34 ZnO samples various origins. A principal component analysis allows sorting three clusters having different properties. correlation discloses most relevant characteristics affecting dissolution: density, agglomerate size specific surface area. Coarse particles dissolve process according their Fine aggregated 2 steps: at primary particles, followed by diffusion quiescent bulk aqueous medium. reaction-diffusion model proposed.