Titania flame synthesis

Kammler, H.K., Jossen, R., Morrison, P.W., Jr., Pratsinis, S.E., and Beaucage, G., The effect of external electric fields during flame synthesis of titania, Powder TechnoL, 310, 135-136, 2003. 

Tsantilis, S., Kammler, H.K., and Pratsinis, S.E., Population balance modeling of flame synthesis of titania nanoparticles, Chem. Eng. Set, 57, 2139, 2002. Madler, L., Stark, W.J., and Pratsinis, S.E., Simultaneous deposition of Au nanoparticles during flame synthesis of Ti02 and Si02, J. Mater. Res., 18, 115, 2003. Tani, T., Madler, L., and Pratsinis, S.E., Synthesis of zinc oxide/sihea composite nanoparticles by flame spray pyrolysis, J. Mater. Set, 37, 4627, 2002. 

Kammler, H.K., and Pratsinis, S.E., Carbon-coated titania nanoparticles continuous, one-step flame-synthesis, J. Mater. Res., 18, 2670, 2003. 

Yeh CL, Yeh SH, Ma HK (2004) Flame synthesis of titania particles from titanium tetraisopropoxide in premixed flames. Powder Technol 145 1-9... 

To prove the above statement, titania powder synthesis has also been conducted using oxidant stream with different oxygen molar ratio in fiame configurations B and C. Table II lists the results. It can been seen from Table II that oxygen mole fraction in the oxidant has more marked effects on particle size and rutile content in fiame C than in flame B, attributed to the total enclosure of fuel and precursor within the O2 flow under configuration of C. With the increase of oxygen firaction in the oxidant, the rutile content of particles synthesized in flame C decreases until the pure anatase particles are... 

Active heterogeneous catalysts have been obtained. Examples include titania-, vanadia-, silica-, and ceria-based catalysts. A survey of catalytic materials prepared in flames can be found in [20]. Recent advances include nanocrystalline Ti02 [24], one-step synthesis of noble metal Ti02 [25], Ru-doped cobalt-zirconia [26], vanadia-titania [27], Rh-Al203 for chemoselective hydrogenations [28], and alumina-supported noble metal particles via high-throughput experimentation [29]. 

Various methods are applied to the synthesis of titania particles including sol-gel method, hydrothermal method [2], citrate gel method, flame processing and spray pyrolysis [1]. To utilize titania as a photocatalyst, the formation of ultrafme anatase titania particles with large crystallite size and large surface area by various ways has been studied [4]. 

In this work, flame spray pyrolysis was applied to the synthesis of titania particles to control the crystal structure and crystallite size and compared with the particle prepared by the conventional spray pyrolysis... 

A process called flame combustion synthesis is widely used to manufacture catalysts containing carbon black, fumed silica, or titania [277-279]. 

W.J. Stark, K. Wegner, S.E. Pratsinis, A. Baiker, Flame Aerosol Synthesis of Vanadia-Titania Nanoparticles Structural and Catalytic Properties in the Selective Catalytic Reduction of NO by NH3, J. Catal. 197 (2001) 182. 

The observation of individual AST particles with the hydrodynamic diameter of 10-20 nm (Figure 2.56), i.e., smaller than the average geometrical diameter of primary particles, is untypical for the aqueous suspensions of fumed silica, alumina, titania, or binary oxides (Gun ko et al. 2001e). This result can be caused by a very broad size distribution of primary particles of AST (broad primary particle size distribution is characteristic for nanooxides with a low specific surface area [vide supra Degussa 1997]). Therefore, one can assume that primary AST particles of strongly different sizes are characterized by different contributions of titania, alumina, and silica, since they can be formed in different zones of the flame during the synthesis. 

---