Toward a Comprehensive Model of the Synthesis of TiO2 Particles from TiCl4

详细信息    查看全文

• 作者：Richard H. West ; Matthew S. Celnik ; Oliver R. Inderwildi ; Markus Kraft ; Gregory J. O. Beran ; William H. Green
• 刊名：Industrial & Engineering Chemistry Research
• 出版年：2007
• 出版时间：September 12, 2007
• 年：2007
• 卷：46
• 期：19
• 页码：6147 - 6156
• 全文大小：273K
• 年卷期：v.46,no.19(September 12, 2007)
• ISSN：1520-5045

文摘

The combustion of TiCl₄ to synthesize TiO₂ nanoparticles is a multimillion tonne per year industrialprocess. The objective of this paper is to further the understanding of this process. Work toward three aspectsof this multiscale problem is presented herein: gas-phase chemistry, surface chemistry, and the solution ofa multidimensional population balance problem coupled to detailed chemical mechanisms. Presented hereis the first thermodynamically consistent mechanism with physically realistic elementary-step rate constantsby which TiCl₄ is oxidized to form a stable Ti₂O_xCl_y species that lies on the path to formation of TiO₂nanoparticles. Second, progress toward a surface chemistry mechanism based on density functional theory(DFT) calculations is described. Third, the extension of a stochastic two-dimensional (surface-volume)population balance solver is presented. For the first time, the number and size of primary particles withineach agglomerate particle in the population is tracked. The particle model, which incorporates inception,coagulation, growth, and sintering, is coupled to the new gas-phase kinetic model using operator splitting,and is used to simulate a heated furnace laboratory reactor and an industrial reactor. Using the primary particleinformation, transmission electron microscopy (TEM)-style images of the particles are generated, demonstratingthe potential utility of first-principles modeling for the prediction of particle morphology in complex industrialsystems.