Effect of sodium carbonate addition on carbothermic reduction of ilmenite concentrate  

添加剂Na_(2)CO_(3)对钛精矿碳热还原的影响

作　　者：Xiao-dong LÜ Dan CHEN Yun-tao XIN Wei LÜ Xue-wei LÜ 吕晓东;陈丹;辛云涛;吕炜;吕学伟(重庆大学材料科学与工程学院,重庆400044;重庆大学钒钛冶金及新材料重庆市重点实验室,重庆400044)

机构地区：[1]College of Materials Science and Engineering,Chongqing University,Chongqing 400044,China [2]Chongqing Key Laboratory of Vanadium−Titanium Metallurgy and Advanced Materials,Chongqing University,Chongqing 400044,China

出　　处：《Transactions of Nonferrous Metals Society of China》2022年第3期1010-1018,共9页中国有色金属学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (No. U1902217)。

摘　　要：The enhanced reduction mechanism and kinetics of different Na_(2)CO_(3) additions in the carbothermic reduction of ilmenite concentrate were investigated.The reduction process was carried out at different heating rates in a thermogravimetry facility,and the kinetics was studied using the Starink method.The results indicate that Na_(2)CO_(3) addition enhanced the reduction effect as well as reduced the initial temperature of the reaction and the activation energy by increasing reactant activity in reactant form;however,it deteriorated the late-stage kinetic conditions by generating a molten phase,thereby reducing the reaction rate in the late stages of reduction.The average apparent activation energies of ilmenite concentrate with 0%,3%,and 6%Na_(2)CO_(3) are 447,289,and 430 kJ/mol,respectively.The results from kinetics parameters confirm that Na_(2)CO_(3) addition accelerated the reduction kinetics;however,excessive addition worsened the reduction kinetics.研究添加不同含量的Na_(2)CO_(3)对钛精矿强化还原机理和动力学的影响,以不同的升温速率进行还原过程,并采用Starink方法研究其动力学。结果表明:Na_(2)CO_(3)的加入强化还原效果,并通过以反应物的形式增加其活性来降低还原反应的初始温度和表观活化能;然而,Na_(2)CO_(3)的加入会形成熔融相恶化还原后期的动力学条件,从而降低还原后期的反应速率。当Na_(2)CO_(3)添加量分别为0%、3%和6%时,还原过程的平均表观活化能为447、289和430 kJ/mol。动力学参数表明,添加Na_(2)CO_(3)能改善还原动力学条件,但添加过量会恶化还原动力学条件。

关 键 词：ilmenite concentrate non-isothermal kinetics reduction mechanism apparent activation energy 

分 类 号：TF823[冶金工程—有色金属冶金]