Aerosol Flame Reactors for the Synthesis of Nanoparticles

Abstract

This paper presents an overview of recent basic research on flame aerosol reactors for the gas-phase synthesis of nanoparticles. Emphasis is placed on flame reactor technology as it is widely used in industry for the large-scale manufacture of oxide and carbon nanoparticles. The importance of reactant gas mixing, additives and external electric fields in flame technology is highlighted for the control of product particle properties by affecting the chemistry, temperature and collision histories. Laser-induced fluorescence (LIF), Fourier transform infrared spectroscopy (FTIR) and thermophoretic sampling are addressed as some of the promising diagnostic tools in flame aerosol research and even for on-line process control. Recent work on aerosol dynamics modeling is presented, and the growing importance of computational fluid dynamics (CFD) aimed at better understanding the particle formation and growth mechanisms in flames is emphasized, focusing on the synthesis of non-aggregated nanoparticles.