红格钒钛磁铁矿氧化物相转变及非等温氧化动力学

Phase Transformation and Non-isothermal Oxidation Kinetics of Hongge Vanadium-Bearing Titanomagnetite

在对红格钒钛磁铁矿基础特性研究基础上,探讨了其球团氧化过程物相的存在形式和转变过程,并通过热分析法研究了红格矿非等温氧化动力学.结果表明:红格钒钛磁铁矿属于高铬型钒钛磁铁矿,Cr_2O_3的质量分数为1.48%,连晶强度为625 N;主要物相组成为磁铁矿、钛磁铁矿、钒磁铁矿、铬铁矿;温度低于300℃时其氧化速率缓慢;球团氧化过程有价组元物相迁移变化历程为:Fe_3O_4→Fe_2O_3;Fe_2VO_4→(Cr_(0.15)V_(0.85))_2O_3;Fe_(2.75)Ti_(0.25)O_4→FeTiO_3→Fe_9TiO_(15);FeCr_2O_4→(Fe_(0.6)Cr_(0.4))_2O_4,Fe_(0.7)Cr_(1.3)O_3,(Cr_(0.15)V_(0.85))_2O_3.红格矿非等温氧化动力学研究表明:当升温速率为10℃/min时,温度在220~380℃,380~500℃和500~800℃时,反应活化能分别为47.02,14.95和30.36 kJ·mol^(-1).

The existence form and phase transformation of Hongge vanadium-bearing titanomagnetite（HVTM） pellets during oxidation process were investigated based on the study of fundamental characteristics of the ore.The non-isothermal oxidation kinetics of HVTM was also studied by the thermogravimetry.The results indicated that the HVTM is high chromium vanadium-bearing titanomagnetite with 1.48wt% Cr2O3 and its crystal stock strength is 625 N,the ore mainly consists of magnetite,titanomagnetite,coulsonite and chromite.The HVTM oxidizes slowly below 300 ℃.Phase transformation behavior of valuable elements is as follows： Fe3O4→Fe2O3,Fe2VO4 →（Cr0.15V0.85）2O3,Fe2.75Ti0.25O4 →FeTiO3 →Fe9TiO15,FeCr2O4 →（Fe0.6Cr0.4）2O4,Fe0.7Cr1.3O3 and（Cr0.15V0.85）2O3.The results of non-isothermal oxidation kinetics of HVTM showed that when the HVTM oxidized at 220~380 ℃,380~500 ℃ and 500~800 ℃with a heating rate of 10 ℃·min^-1,the activation energy are 47.02,14.95 and 30.36 kJ·mol^-1,respectively.