氢氧化钠亚熔盐体系分解铬铁矿的工艺研究  

Production process of extraction chromium from chromite with sub-molten sodium hydroxide

作　　者：江春立 宋红军 韩彪 赵伟 董立春[2] 黄世友 文丰玉 

机构地区：[1]广西环境保护科学研究院,广西南宁530000 [2]重庆大学化学化工学院

出　　处：《无机盐工业》2016年第7期39-43,共5页Inorganic Chemicals Industry

摘　　要：研究了氢氧化钠亚熔盐体系氧压浸出铬铁矿工艺的主要作用因素对铬浸出率的影响,确定了最佳的工艺参数。结果表明,氢氧化钠亚熔盐氧压浸出过程,对铬浸出影响最显著的因素是温度和氧压力;在铬铁矿粒径为0.038~0.048 mm、矿碱质量比为1∶7、搅拌速度为650 r/min条件下,氢氧化钠亚熔盐氧压浸出铬的最佳反应条件为:浸出温度为245℃、碱浓度为65%(质量分数)、氧气压力为0.8 MPa、反应时间为480 min。在该条件下铬的浸出率为99%以上,活化能为51.49 k J/mol,动力学方程为1-2/3x-(1-x)^(2/3)=2 124.73 PO20.85×e^(-51 490/RT)×t。The main extraction factors of chromite ore were studied by decomposing the chromium in Na OH sub-molten salt system,and the optimum process parameters were deterimined.Results showed that reaction temperature and oxygen partial pressure were the most significant factors on chromium extraction efficiency.Under the conditions of particle size among0.038~0.048 mm,mass ratio of ore to Na OH of 1∶7,and agitation speed of 650 r/min,the optimal conditions of decomposing the chromium in Na OH sub-molten salt system were obtained as follows：the reaction temperature was 245 ℃,the Na OH solution content was 65%（mass fraction）,the oxygen partial pressure was 0.8 MPa,and the reaction time was 480 min.Under the optimal conditions,the chromium extraction rate was above 99%.The macro-kinetic investigation revealed that the leaching process was controlled by reactant diffusion in the solid product layer and described by 1-2/3x-（1-x）^2/3=2 124.73 ×PO2^0.85×e^-51 490/RT×t with apparent activation energy of 51.49 k J/mol.

关 键 词：铬铁矿 氢氧化钠 亚熔盐 动力学 

分 类 号：TQ136.11[化学工程—无机化工]