SCI和EI收录∣中国化工学会会刊

›› 2014, Vol. 22 ›› Issue (10): 1105-1110.DOI: 10.1016/j.cjche.2013.04.001

• 催化、动力学与反应工程 • 上一篇    下一篇

Kinetics for Preparation of K2Ti2O5 Using TiO2 Microparticles and Nanoparticles as Precursors

Hanbing He1,2, Chang Liu1, Xiaohua Lu1   

  1. 1 State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing University of Technology, Nanjing 210009, China;
    2 Division of Energy Science, Luleå University of Technology, Luleå 971 87, Sweden
  • 收稿日期:2013-01-21 修回日期:2013-04-22 出版日期:2014-10-28 发布日期:2014-12-01
  • 通讯作者: Xiaohua Lu
  • 基金资助:
    Supported by the Chinese National Key Technology Research and Development Program (2006AA03Z455), the National Natural Science Foundation of China (20976080, 21136004) and the National Basic Research Program of China (2009CB226103).

Kinetics for Preparation of K2Ti2O5 Using TiO2 Microparticles and Nanoparticles as Precursors

Hanbing He1,2, Chang Liu1, Xiaohua Lu1   

  1. 1 State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing University of Technology, Nanjing 210009, China;
    2 Division of Energy Science, Luleå University of Technology, Luleå 971 87, Sweden
  • Received:2013-01-21 Revised:2013-04-22 Online:2014-10-28 Published:2014-12-01
  • Supported by:
    Supported by the Chinese National Key Technology Research and Development Program (2006AA03Z455), the National Natural Science Foundation of China (20976080, 21136004) and the National Basic Research Program of China (2009CB226103).

摘要: The formation mechanism of K2Ti2O5 was investigated with TiO2 microparticles and nanoparticles as precursors by the thermogravimetric (TG) technique. Amethod of directmultivariate non-linear regression was applied for simultaneous calculation of solid-state reaction kinetic parameters fromTG curves. TG results showmore regular decrease from initial reaction temperature with TiO2 nanoparticles as raw material compared with TiO2 microparticles, while mass losses finish at similar temperatures under the experimental conditions. From the mechanism and kinetic parameters, the reactions with the two materials are complex consecutive processes, and reaction rate constants increase with temperature and decrease with conversion. The reaction proceedings could be significantly hindered when the diffusion process of reactant species becomes rate-limiting in the later stage of reaction process. The reaction active sites on initial TiO2 particles and formation of product layers may be responsible to the changes of reaction rate constant. The calculated results are in good agreement with experimental ones.

关键词: Solid-state, Kinetics, Particle, Reaction, Non-linear regression

Abstract: The formation mechanism of K2Ti2O5 was investigated with TiO2 microparticles and nanoparticles as precursors by the thermogravimetric (TG) technique. Amethod of directmultivariate non-linear regression was applied for simultaneous calculation of solid-state reaction kinetic parameters fromTG curves. TG results showmore regular decrease from initial reaction temperature with TiO2 nanoparticles as raw material compared with TiO2 microparticles, while mass losses finish at similar temperatures under the experimental conditions. From the mechanism and kinetic parameters, the reactions with the two materials are complex consecutive processes, and reaction rate constants increase with temperature and decrease with conversion. The reaction proceedings could be significantly hindered when the diffusion process of reactant species becomes rate-limiting in the later stage of reaction process. The reaction active sites on initial TiO2 particles and formation of product layers may be responsible to the changes of reaction rate constant. The calculated results are in good agreement with experimental ones.

Key words: Solid-state, Kinetics, Particle, Reaction, Non-linear regression