风化壳淋积型稀土矿浸矿过程的离子交换模型

以硫酸铵溶液作为浸矿剂,对风化壳淋积型稀土矿进行了杯浸试验,结果表明,随着硫酸铵浓度增加,液相稀土离子浓度越高,当硫酸铵浓度超过40.00 mmol/L时,液相稀土离子浓度不再随着硫酸铵浓度增加而变化。运用Kerr模型、Vanselow模型和Gapon模型描述液相铵根离子交换固相稀土离子的离子交换过程,结合试验数据,给出了3种模型的选择系数计算方法,并分析了3种模型的计算值与试验值的误差。结果发现,Gapon模型计算误差较大,Kerr模型和Vanselow模型计算误差相当,由于Kerr模型更为简单,便于分析,建议采用Kerr模型描述液相铵根离子交换固相稀土离子的离子交换过程。

An Ion Exchange Model for Leaching Process of Weathered Crust Elution-deposited Rare Earth

With ammonium sulphate solution as a leaching agent, a cup leaching test was conducted for the weathered crust elution-deposited rare earth ore. It is found that the liquid-phase rare earth ion concentration increased with the increasing of ammonium sulfate concentration. When the concentration of ammonium sulfate exceeded 40.00 mmol/L, there was no more change in the liquid-phase rare earth ion concentration with the increasing of ammonium sulfate concentration. The Kerr model,Vanselow model and Gapon model were used to describe the ion exchange process between liquid-phase ammonium ion and solid-phase rare earth ions. Combined with the experimental data, a calculation method for selecting coefficients of three models was presented, and error between the calculated values of three models and experimental results were analyzed. Results showed that the error from the Gapon model calculation was relatively greater than that from Kerr and Vanselow model calculations, the later two models with nearly same margin of error. It is recommended that Kerr model be adopted to describe the ion exchange process due to its simple operation.