主要研究不同质量比的Fe2O3-NiO在氢气气氛下还原过程的非等温动力学.根据热分析动力学研究方法,结合样品的质量损失曲线,获得了样品在非等温还原过程中的动力学曲线,并确定Fe2O3-NiO体系在氢气气氛下还原过程的最佳机理函数(G(α)=[-ln(1-α)]4),过程受随机成核和随后生长机理控制.结果表明:当样品中Fe2O3-NiO质量比从1∶2变化到2∶1时,还原反应过程的活化能从249.821 kJ/mol增加至390.074 kJ/mol;随着体系中NiO含量增加,还原反应开始的温度逐渐降低,还原产物物相由铁纹石相(Fe,Ni)和镍纹石相(Fe,Ni)逐渐转变为镍铁合金相(FeNi3),产物微观颗粒尺寸变得不均匀.通过建立数学模型,验证了反应过程中反应分数的模型计算值与实验测量值具有良好的相关性.
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.
参考文献
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%