(1. 昆明理工大學(xué) 省部共建復(fù)雜有色金屬資源清潔利用國家重點實驗室，昆明 650093；
2. 昆明理工大學(xué) 冶金與能源工程學(xué)院，昆明 650093)
摘 要: 主要研究不同質(zhì)量比的Fe2O3-NiO在氫氣氣氛下還原過程的非等溫動力學(xué)。根據(jù)熱分析動力學(xué)研究方法，結(jié)合樣品的質(zhì)量損失曲線，獲得了樣品在非等溫還原過程中的動力學(xué)曲線，并確定Fe2O3-NiO體系在氫氣氣氛下還原過程的最佳機理函數(shù)(G(α)=[-ln(1-α)]4)，過程受隨機成核和隨后生長機理控制。結(jié)果表明：當樣品中Fe2O3-NiO質(zhì)量比從1:2變化到2:1時，還原反應(yīng)過程的活化能從249.821 kJ/mol增加至390.074 kJ/mol；隨著體系中NiO含量增加，還原反應(yīng)開始的溫度逐漸降低，還原產(chǎn)物物相由鐵紋石相(Fe,Ni)和鎳紋石相(Fe,Ni)逐漸轉(zhuǎn)變?yōu)殒囪F合金相(FeNi3)，產(chǎn)物微觀顆粒尺寸變得不均勻。通過建立數(shù)學(xué)模型，驗證了反應(yīng)過程中反應(yīng)分數(shù)的模型計算值與實驗測量值具有良好的相關(guān)性。
關(guān)鍵字: 還原動力學(xué)；Fe2O3-NiO；鎳鐵合金；機理函數(shù)
（1. State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming 650093, China;
2. Faculty of Metallurgy and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, China）
Abstract:For the different mass ratio of Fe2O3 and NiO, the non-isothermal kinetics of reduction process using hydrogen as agent was investigated. According to the method of thermal analysis kinetics, combined with mass loss curves of sample, the deoxidization kinetics of the sample in reduction of non-isothermal process and the best mechanism function(G(α)=[-ln(1-α)]4) for reduction process of Fe2O3-NiO system in hydrogen atmosphere were obtained. It is found that the reduction is dominated by the random nucleation and then growth process. The results show that when the Fe2O3-NiO mass ratio is changed from 1:2 to 2:1, the activation energies of reduction process increase from 249.821 kJ/mol to 390.074 kJ/mol. With the content of NiO increasing，the initial temperature of reduction reaction reduces gradually, the Kamacite(Fe, Ni) and the Taenite(Fe, Ni) gradually convert into the awaruite (FeNi3). The particle-size of the product after reduction become, nonuniform. Based on the built mathematical model, the calculated values of mathematical model and the measured values of reaction fraction are fit in well.
Key words: reduction kinetics; Fe2O3-NiO; Fe-Ni alloy; mechanism function
