磷矿中稀土浸出的动力学研究

Kinetic Study on Leaching of RE in Phosphorite

研究了硝酸浸出磷矿中稀土的动力学,考察了温度、浓度、粒度对稀土浸出率的影响。结果表明,提高温度和浓度、减小粒度均能提高稀土浸出率。浸出过程符合未反应收缩核模型,受界面化学反应控制,表观活化能为70.6 kJ/mol,表观反应级数为0.83级。

The leaching kinetics of RE from pospheric ore by nitric acid was studied.The effecting factors,such as temperature,acid concentration and particle size,on RE leaching rate were investigated.The result showed that increasing temperature and acid concentration,reducing particle size could accelerate the leaching rate of RE.An unreacted shrinking core model was used to describe the leaching process and the kinetic equation was obtained.The leaching process was controlled by the interfacial chemical reaction.The apparent activation energy was calculated to be 70.6 kJ/mol,and the apparent reaction order was 0.83.