(中南大學(xué) 資源加工與生物工程學(xué)院, 長(zhǎng)沙 410083)
摘 要: 根據(jù)一水硬鋁石(α-AlOOH)分解前后的X射線衍射(XRD)譜, 判斷其熱分解后主要生成α-Al2O3。 分別用Coats-Redfern積分法和Kissinger方法處理了不同升溫速率下一水硬鋁石的差熱曲線, 兩種方法得到的熱分解反應(yīng)動(dòng)力學(xué)參數(shù)非常接近, 計(jì)算所得的活化能分別為254.54kJ/mol和244.08kJ/mol, 并推斷了反應(yīng)的動(dòng)力學(xué)模型和反應(yīng)機(jī)理。 研究表明一水硬鋁石的熱分解符合Mample單行法則, 相對(duì)應(yīng)的機(jī)理為隨機(jī)成核和隨后增長(zhǎng)。
關(guān)鍵字: 一水硬鋁石; 熱分析; 反應(yīng)動(dòng)力學(xué); 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


