Sol-Gel法制备掺Fe莫来石的非等温动力学研究  

Non-isothermal kinetics of mullite with Fe prepared by Sol-Gel method

作　　者：白玉云 丁学勇 齐渊洪[2] 居天华 刘金生 BAI Yuyun;DING Xueyong;QI Yuanhong;JU Tianhua;LIU Jinsheng(School of Metallurgy,Northeastern University,Shenyang 110819,Liaoning,China;State Key Laboratory of Advanced Steel Processes and Materials,Centre Iron and Steel Research Institute,Beijing 100081,China)

机构地区：[1]东北大学冶金学院,辽宁沈阳110819 [2]钢铁研究总院先进钢铁流程及材料国家重点实验室,北京100081

出　　处：《钢铁研究学报》2022年第4期317-325,共9页Journal of Iron and Steel Research

基　　金：国家重点研发计划资助项目(2017YFB0603801)。

摘　　要：为深入了解回转窑结圈的反应动力学机制,结合Sol-Gel法和燃烧法合成了掺杂量(质量分数)为0%、9%、12%和15%Fe的莫来石前驱体。利用DSC、XRD、SEM以及EDS对实验过程的物相转变、微晶变化进行分析,采用非等温动力学模型(KAS、Augis-Bennett方程)和GaussAmp拟合方程计算了活化能E;、Avrami指数n和拟合速率方程f(t)。结果发现,铁的加入会降低莫来石结晶温度,使液相形成温度降低,莫来石纳米晶呈三维扩散长大,晶体由形状良好的等轴球形发展为枝晶状,形成了枝晶互锁结构,对动力学参数进行计算,得E;为941.49 kJ/mol,n为1.46,拟合反应为自催化反应。研究结果表明Fe的加入会促使莫来石反应活化能和液相形成温度降低,导致物料板结,结圈加剧。In order to deeply understand the reaction kinetic mechanism of rotary kiln ring formation,mullite precursors doped with 0 mass%,9 mass%,12 mass%and 15 mass%of Fe were synthesized by Sol-Gel method and combustion method.The phase transformation and microcrystal change in the experimental process were analyzed by DSC,XRD,SEM and EDS,and then the activation energy E;,Avrami index n and fitting rate equation f(t)were calculated by non-isothermal kinetic model(KAS,Augis-Bennett equation)and GaussAmp fitting equation.The results show that the addition of Fe can reduce the crystallization temperature of mullite and the formation temperature of liquid phase.Mullite nanocrystals grow in three-dimensional diffusion,and the crystal develops from a well-shaped equiaxed sphere to a dendritic interlocking structure.By calculating the kinetic parameters,E;of 941.49 kJ/mol,n of 1.46 were obtained,the fitting reaction is autocatalytic reaction.The results show that the addition of Fe can reduce the activation energy of mullite reaction and the formation temperature of liquid phase,which leads to the hardening of materials and aggravation of ring formation.

关 键 词：溶胶凝胶法 莫来石 反应动力学 结圈 

分 类 号：TF04[冶金工程—冶金物理化学]