Synthesis of nanooxides in two-phase laminar flames

This paper deals with a method for production of nanopowders of high-melting metal oxides by burning the starting metal powders in a laminar disperse flame. The method is called gas-dispersed synthesis. The combustion-zone structure for a laminar diffusion dispersed flame and for a laminar flame of premixed fuel and oxidizer was studied experimentally. Information was obtained on the temperature of combustion gases and its spatial distribution, the temperatures of the burning particles and of the condensed combustion products, and the combustion regimes of metal particles. The dependence of the properties of the resulting oxides on the flame and combustion-zone parameters and the mechanism of particle combustion is studied. Based on the results, an attempt is undertaken to reproduce the mechanisms of formation and growth of the condensed phase under conditions of laminar diffusion flames. The mass-averaged particle size of the oxide powders is estimated.