KOH-KNO3二元亚熔盐分解铬铁矿的实验研究  

Experimental study on chromite ore decomposition by KOH-KNO_3 binary sub-molten salt

作　　者：张洋[1] 孙峙[1] 郑诗礼[1] 张懿[1] 

机构地区：[1]中国科学院过程工程研究所

出　　处：《化工进展》2008年第7期1042-1047,共6页Chemical Industry and Engineering Progress

基　　金：国家“863”计划项目(2006AA06Z129)

摘　　要：通过采用添加硝酸钾的方法以强化铬铁矿的KOH亚熔盐氧化分解过程。实验考察了碱矿比、盐矿比、氧分压、气体流量以及反应温度等工艺参数对铬铁矿分解过程的影响,以明确KOH-KNO3二元亚熔盐分解铬铁矿的分解条件。结果表明,反应温度与碱矿比对铬转化率影响显著,氧气分压与气体流量的影响次之。在KOH亚熔盐体系中加入KNO3后,碱矿比可由4∶1降到2∶1;铬铁矿分解过程的动力学方程符合1+2(1-x)-3(1-x)2/3=kt,表观活化能为55.63 kJ/mol,为内扩散控制过程。KNO3通过强化氧传递过程而明显促进了铬铁矿的分解。Potassium nitrate was added to intensify the chromite decomposition process by KOH sub-molten salt.The effects of the mass ratio of alkali-to-ore,the mass ratio of KNO3-to-ore,oxygen partial pressure,gas flow rate and reaction temperature on the decomposition of chromite ore were experimentally studied to determine the chromite decomposition parameters by KOH-KNO3 binary sub-molten salt.The results showed that reaction temperature and the ratio of alkali-to-ore were most significant factors on the chromium conversion efficiency.The effects of oxygen partial pressure and flow rate were less significant.The ratio of KOH-to-ore decreased from 4∶1 to 2∶1 after adding KNO3 to KOH sub-molten salt.The kinetics equation of chromite decomposition was＂1＋2（1-x）-3（1-x）2/3=kt＂,and the apparent activation energy was 55.63 kJ/mol,which agreed with the inner-diffusion control model.KNO3 played a significant role in oxygen transfer,which obviously promoted the decomposition of chromate ore.

关 键 词：铬铁矿 KOH-KNO3 亚熔盐 分解 

分 类 号：TQ136.11[化学工程—无机化工] TF111[冶金工程—冶金物理化学]