CaO 对铁酸锌还原过程中锌迁移机制和动力学的影响  

Effect of CaO on zinc migration mechanism and kinetics during zinc ferrite reduction

作　　者：王伟安 邱国兴 王建立 贺芸 李小明[1] Wei-an WANG;Guo-xing QIU;Jian-li WANG;Yun HE;Xiao-ming LI(School of Metallurgical Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China)

机构地区：[1]西安建筑科技大学冶金工程学院,西安710055

出　　处：《Transactions of Nonferrous Metals Society of China》2023年第9期2832-2842,共11页中国有色金属学报（英文版）

基　　金：This work is supported by the Natural Science Basic Research Plan in Shaanxi Province,China(No.2019JLM-35);the Key Laboratory of Ecological Metallurgy of Multimetallic Mineral(Northeastern University)of the Ministry of Education,China.

摘　　要：研究CaO、还原时间和还原温度对Zn迁移机制和动力学模型的影响。结果显示,CaO通过促进中间产物ZnO在Fe和CaO混合物表面的析出和富集,提高锌的挥发率。添加CaO后,ZnFe_(2)O_(4)还原步骤为ZnFe_(2)O_(4)→Ca2Fe_(2)O_(5)→FeO→Fe。ZnFe_(2)O_(4)还原的挥发模型从一阶化学反应模型(不添加CaO)转变为三维扩散模型(添加CaO),表观活化能从313.9 kJ/mol降低到91.77 kJ/mol,为锌的高效还原和挥发提供有利条件。Effects of CaO,reduction time and reduction temperature on the Zn migration mechanism and kinetic model were studied.Results show that CaO improves the volatilization rate of Zn by promoting the precipitation and enrichment of the intermediate product ZnO on the surface of the mixture of Fe and CaO.The reduction steps of ZnFe_(2)O_(4)with CaO are ZnFe_(2)O_(4)→Ca2Fe_(2)O_(5)→FeO→Fe.The volatilization model of the reduction of ZnFe_(2)O_(4)was changed from a first-order chemical reaction model(without CaO)to a three-dimensional diffusion model(with CaO),and the apparent activation energy was reduced from 313.9 to 91.77 kJ/mol,providing favorable conditions for the efficient reduction and volatilization of zinc.

关 键 词：含锌粉尘 铁酸锌 还原动力学 迁移机制 直接还原 锌回收 

分 类 号：TF813[冶金工程—有色金属冶金]