Hostname: page-component-cd9895bd7-jn8rn Total loading time: 0 Render date: 2024-12-27T01:33:32.828Z Has data issue: false hasContentIssue false
  • English
  • Français

Electrically Assisted Aerosol Reactors using Ring Electrodes

Published online by Cambridge University Press:  10 February 2011

H. Briesen ,
A. Fuhrmann  and
S. E. Pratsinis
H. Briesen
Affiliation:
Department of Chemical Engineering, University of Cincinnati, Cincinnati, OH 45221-0171
A. Fuhrmann
Affiliation:
Department of Chemical Engineering, University of Cincinnati, Cincinnati, OH 45221-0171
S. E. Pratsinis
Affiliation:
Department of Chemical Engineering, University of Cincinnati, Cincinnati, OH 45221-0171, [email protected]
Get access

Abstract

Nanostructured materials have distinctly different properties than the bulk because the number of atoms or molecules on their surface is comparable to that inside the particles creating a number of new materials and applications. Despite this potential for nanoparticles, very few practical applications have been developed because of the current high cost of these materials ($100/lb). On the other hand, flame aerosol reactors are routinely used for inexpensive production (∼$1/lb) of submicron sized commodities such as carbon blacks, pigmentary titania, fumed silica and preforms for optical fibers in telecommunications. Flame technology can be used also for synthesis of nanoparticles with precisely controlled characteristics. In these reactors, gas mixing is used to widely control the primary particle size and crystallinity of product powders while electric fields can be used to narrowly control the primary, and aggregate particle size and crystallinity. Here the application of axial electrical fields on a silica producing flame using hexamethyldisiloxane (HMDS) as precursor is presented. Experiments varying the precursor delivery rate corresponding to total production rates of 10, 20 and 30 g/h are presented. Electric fields decreased the particle size by electrostatic dispersion and repulsion of charged particles and by the reduced particle residence time inside the flame.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 520: Symposium P – Nanostructured Powders & Their Industrial Application , 1998 , 3
Copyright
Copyright © Materials Research Society 1998

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Fotou, G.P., Pratsinis, S.E., Baron, P.A., “Coating of Silica Fibers by Ultrafine Particles in a Flame Reactor”, Chem. Eng. Sci. 49, 1651–1662 1994.Google Scholar
Fotou, G.P., Scott, S.J., Pratsinis, S.E., “The Role of Ferrocene in Flame Synthesis of Silica”, Combustion and Flame 101, 529–38g 1995.Google Scholar
Pratsinis, S.E., “Flame Aerosol Synthesis of Ceramic Powders” Prog. Energy Combust. Sci. 24, 197–219 1998.Google Scholar
Pratsinis, S.E., Zhu, W., Vemury, S., “The Role of Gas Mixing in Flame Synthesis of Titania Powders”, Powder Technol. 86, 87–93 1996.Google Scholar
Place, E.R. and Weinberg, F.J., “The Nucleation of Flame Carbon by Ions and the Effect of Electric Fields”, Eleventh Symposium (International) on Combustion, The Combustion Institute, Pittsburgh, PA, 1967.Google Scholar
Vemury, S., Pratsinis, S.E., “Corona-Assisted Flame Synthesis of Ultrafine Titania Particles”, Appl. Phys. Lett. 66, 3275–7 (1995a).Google Scholar
Vemury, S., Pratsinis, S.E., “Dopants in Flame Synthesis of Titania”, J. Amer. Ceram. Soc. 78, 2984–92 (1995b).Google Scholar
Vemury, S., Pratsinis, S.E., Kibbey, L. “Electrically-Controlled Flame Synthesis of Nanophase TiO2, SiO2 and SnO2”, J. Mater. Res. 12, 1031–1042 1997.Google Scholar
Ulrich, G.D., “Flame Synthesis of Fine Particles”, C&EN, 62 (August 6), 22 (1984).Google Scholar