氢氧化锆非等温热分解动力学研究

Kinetics study of non-isothermal decomposition of Zr(OH)_4

利用TG-DTG-DSC技术研究了氢氧化锆非等温热分解过程,应用模型法和非模型法对热分解过程进行了动力学分析,建立了动力学函数,得到了氢氧化锆热分解反应机理。氢氧化锆在氮气中热分解的活化能E=71.26 kJ/mol,指前因子lgA=18.20,机理函数积分式g(α)=[-ln(1-α)]4,微分式f(α)=(1-α)[-ln(1-α)]-3/4,反应机理为随机成核和随后生长。

The non-isothermal pyrolysis of zirconium hydroxide was studied with the TG-DTG-DSC method in this paper. It got the dynamic function and the reaction mechanism of thermal decomposition of zirconium hydroxide. The thermal decomposition kenitics were investigated employing model fitting and non-model fitting. The activity energy for the decoposition reaction of zirconium hydroxide was determined to be E=71.26 kJ/mol in nitrogen atmosphere and the pre-exponential factor of its kinetics equations was calculated to be IgA=18.20. The integral mechanism function is g（a）=[-In（1-a）]^1 and the differential one is f（a）= （1-a）[-In（1-a）^-3/4, the reaction mechanism is proved to be ran- dom nucleation and subsequent growth.