摘要
在HSC6.0计算软件热力学分析的基础上,采用正交实验确定了高磷鲕状赤铁矿酸浸脱磷保铁的最佳工艺,并以最佳工艺为基础进行了酸浸过程中脱磷和铁损反应的动力学研究。热力学分析表明H_2SO_4为最佳酸浸用酸。正交实验得出最佳酸浸条件为:H+浓度为0.5mol/L的H_2SO_4溶液、酸浸时间40min、温度298K、液固比200mL∶14g、搅拌速度100r/min。在该条件下,脱磷率可达98.89%,铁损率仅为0.51%。通过SEM-EDS对酸浸前后高磷鮞状赤铁块矿试样分析表征得出:经H_2SO_4浸出后,磷灰石基本完全溶解,含铁矿相未发生明显反应。动力学分析显示:优化条件下,酸浸脱磷反应在298~328K内符合收缩未反应核模型,浸出过程主要受内扩散控制,表观活化能为11.24kJ/mol;铁损反应在298~328K内遵循收缩未反应核模型,浸出过程主要受化学反应控制,表观活化能为42.24kJ/mol。
Based on the thermodynamic analysis using HSC6.0 software,a series of acid leaching orthogonal experiments of high phosphorus oolitic hematite were carried out and the optimal conditions for phosphorus removal and iron conservation had been obtained.The kinetic analysis of dephosphorization and iron dissolution was also studied under the optimal conditions.The thermodynamic analyses indicate that H2 SO4 is the most appropriate acid for leaching.The optimal leaching conditions are acid concentration of 0.5 mol/L,leaching time of 40 min,reaction temperature of 298 K,liquid-solid ratio of 200 mL∶14 g and stirring speed of 100 r/min.Under such conditions,dephosphorization ratio is up to 98.89% with iron loss ratio of only 0.51%.The high phosphorus oolitic hematite ore sample before and after acid leaching was characterized by SEM-EDS,which indicates that apatite is almost completely dissolved,but iron phase hardly reacts after leaching with sulfuric acid.The kinetic analyses indicate that under the optimal leaching conditions ranging from 298 Kto 328 K,the dephosphorization reaction of acid leaching process is controlled by internal diffusion of shrinking core model and its apparent activation energy is11.24 kJ/mol.The iron loss reaction is controlled by chemical reaction and its apparent activation energy is 42.24 kJ/mol.
出处
《钢铁研究学报》
CAS
CSCD
北大核心
2017年第11期883-891,共9页
Journal of Iron and Steel Research
基金
国家自然科学基金资助项目(51374159)
关键词
高磷鲕状赤铁矿
酸浸
正交实验
脱磷
铁损
动力学
high phosphorus oolitic hematite
acid leaching
orthogonal experiment
dephosphorization
iron loss
kinetics
