(中南大学 资源加工与生物工程学院, 长沙 410083)
摘 要: 根据一水硬铝石(α-AlOOH)分解前后的X射线衍射(XRD)谱, 判断其热分解后主要生成α-Al2O3。 分别用Coats-Redfern积分法和Kissinger方法处理了不同升温速率下一水硬铝石的差热曲线, 两种方法得到的热分解反应动力学参数非常接近, 计算所得的活化能分别为254.54kJ/mol和244.08kJ/mol, 并推断了反应的动力学模型和反应机理。 研究表明一水硬铝石的热分解符合Mample单行法则, 相对应的机理为随机成核和随后增长。
关键字: 一水硬铝石; 热分析; 反应动力学; 活化能
(School of Resources Processing and Bioengineering,
Central South University, Changsha 410063, China)
Abstract:Heat-treatment behavior of diaspore(α-AlOOH) was investigated using differential thermal analysis (DTA) and X-ray diffraction (XRD) techniques. Corundum(α-Al2O3) was obtained after thermal treatment of diaspore above 500℃. Coats-Redfern integral method and Kissinger method were used to analyse the DTA curves of samples at different heating rates, and the calculated kinetic parameters for thermal decomposition reaction of diaspore from the two methods are rather close to each other, as the calculated activation energies are 254.54kJ/mol and 244.08kJ/mol, respectively. The results indicate that the decomposition of diaspore accords with the Mample principle and the corresponding mechanism is the random nucleus and the consequent growth.
Key words: diaspore; thermal analysis; reaction kinetics; activation energy