Improve the Applicability of Rate Equation Based on the Model of Diffusion under Non-isothermal Conditions

Abstract:

Rate equation of non-isothermal kinetics of solid decomposition involving the factors of the pressure of gaseous product, the equilibrium pressure, temperature and structure parameters of solid is deduced according to the model of the diffusion of gaseous product. A validity function in the rate equation of non-isothermal kinetics is defined which represents the influence of these factors on the diffusion rate. The effect of the validity function on the diffusion rate are studied, based on the results of thermal analysis of decomposition of calcium carbonate at different heating rates. It is shown that it is possible to improve the validity of the rate equation of non-isothermal kinetics if the effect is taken into account.

• Periodical: Advanced Materials Research (Volumes 233-235)
• Pages: 1659-1664
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.233-235.1659
• Online since: May 2011
• Authors: Guang Lei Tan, Qi Wang, Hong Xia Zheng, Dan Tang, Song Zhang, Zhong Suo Liu
• Keywords: Diffusion, Equilibrium Pressure, Non-Isothermal Kinetics, Structure Parameters of Solid

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