Electro-thermal nanoparticle generator

Reference Number: K 05-01

Inventors: Bossmann, Stefan H.; Bora, Norbert

USPTO Link: 7454893

Invention Summary

The current invention is directed generally to a device and method for the controlled generation of nanoparticles, and specifically to a nanoparticle generator capable of controlling the mass of the particles produced. It should be understood that although the classic definition for a nanoparticle is a particle possessing a diameter, which is smaller than or equal to 100 nm, the nanoparticle particles produced by and in accordance with the current invention can have diameters that are larger than this standard definition by at least an order of magnitude.

The nanoparticle generator of the current invention allows for the production of a combined gas-solid particle stream with a variable mass of solid particles from at least one fuel. The nature of the charged nanoparticles and the fuel are not essential to the present invention. For example, in one embodiment the nanoparticle generator of the current invention is designed to produce nanoparticles comprising black carbon/soot. Although the terms "soot", "carbon black" and "nanoparticles" are used conterminously herein, it should be understood that other types of nanoparticles may be produced.

Black carbon/soot is formed in a combustion process where hydrocarbon compounds or a mixture of hydrocarbon compounds is oxidized at substoichiometric conditions. Nanoparticles produced in a combustion process, such as by the burning of hydrocarbons, are generated in the temperature range of about 1000 K to 2500 K. The average time interval for the formation of nanoparticles of soot is a few milliseconds. During this time period the formation of solid nanoparticles with more than 10.sup.5 amu (atomic mass unit) takes place out of hydrocarbon compounds with a molecular mass of less than 100 amu. Because of the release of hydrogen during combustion, nanoparticles produced by the device of the current invention have a lower hydrogen ratio when compared with the introduced fuel. Accordingly, several reactions must take place to lead to the contrary observations of particle growth and hydrogen loss.