模拟磷矿脱镁废水中镁离子的交换动力学研究

Simulation Study on Ion Exchange Kinetics of Magnesium Ion in Demagging Liquor of Phosphate Ore

用动边界模型积分方程描述模拟磷矿脱镁废水中Mg2+在001×7×7型树脂上的有限浴交换动力学,得到了动力学总方程.Mg2+的交换过程属颗粒扩散控制,表观活化能为23.45kJ·mol-1,Mg2+的表观反应级数为0.68.

The ion exchange kinetics with changing bulk concentration of Mg2+ on strong acid resins (001 x 7 x 7) was studied. Increasing the initial concentration of Mg2+ and reducing the particle radius can accelerate the exchange rate of Mg2+. After reaching 315 r (.) min(-1), the stirring speed has little effect on the exchange rate. An integrating equation of moving boundary model was used to describe the kinetics with changing bulk concentration of Mg2+, and the overall kinetical equation was obtained. The ion exchange process of Mg2+ is controlled by ion diffusion through particles. The apparent activation energy is calculated to be 23.45 kJ (.) mol(-1), and apparent reaction order of Mg2+ is 0.68.