Transfer Processes as a Physical Foundation of Spray Pyrolysis of Micron-Sized Droplets of Solutions

Abstract

The efficiency of the process of spray pyrolysis allowing one to obtain nanoparticles from micron-sized droplets of solutions is determined by the processes of mass transfer in a droplet and of heat and mass exchange in a vapor–gas mixture. It is shown that the slowest and most important process of transfer is evaporation of the droplet. Nucleation of nanoparticles in a supersaturated solution and their growth proceed much more rapidly. The lifetime of the droplet in an aerosol reactor determines the morphology of an ensemble of nanoparticles by coalescence or Brownian diffusion of nanoparticles.