(388i) Computational Investigation of Nanoparticle Synthesis by Flame Spray Pyrolysis

Arto J. Gröhn, Sotiris E. Pratsinis and Karsten Wegner

Particle Technology Laboratory, Swiss Federal Institute of Technology (ETH) Zurich, Sonneggstrasse 3, CH-8092 Zurich, Switzerland.

Flame Spray Pyrolysis (FSP) is a promising method for production of ceramic nanoparticles at the industrial level (Strobel et al., 2007). In order to assist scale-up from the current laboratory process and optimize reactor design, a computational fluid dynamics (CFD) model has been constructed (Gröhn et al., 2012). Taking zirconia nanoparticle synthesis as a case study, the model accounts for spray atomization of the liquid raw material (precursor), combustion and fluid dynamics as well as nanoparticle growth by the aerosol dynamics.

Using a commercial CFD solver, product nanoparticle characteristics are predicted without adjustable parameters or need of experimental input data. By assuming immediate particle formation on precursor oxidation and a self-preserving particle size distribution a robust and computationally feasible description of the process could be employed. The model has been validated with measurements of fuel spray characteristics, flow fields, temperature profiles and primary particle sizes. To obtain insight into the FSP process for scale-up the model has been extended to include both laboratory- and pilot-scale reactor geometries.

References:

Strobel, R. and Pratsinis, S.E. Flame aerosol synthesis of smart nanostructured materials. Journal of Materials Chemistry, 2007. 17, 4743-4756.

Gröhn, A.J. Pratsinis, S.E. and Wegner, K. Fluid-particle dynamics during combustion spray aerosol synthesis of ZrO₂. Chemical Engineering Journal, 2012. 10.1016/j.cej.2012.02.093.