聚丙烯腈基钛酸钾球形复合吸附剂的制备及其对Sr2+的吸附性能研究

以钛酸钾（KTiO）为有效成分、聚丙烯腈（PAN）为基体，制备了聚丙烯腈基钛酸钾球形复合吸附剂（PAN-KTiO）。采用扫描电镜（SEM）、X射线衍射仪（XRD）等对PAN-KTiO进行了表征，并通过静态吸附实验，研究了接触时间、pH值、竞争离子、Sr²⁺初始浓度等对PAN-KTiO吸附Sr²⁺效果的影响，分析了吸附过程的反应动力学和吸附等温线。结果表明，PAN-KTiO对Sr²⁺的吸附平衡时间约为24 h，PAN-KTiO吸附Sr²⁺时，溶液最佳pH值约为6.55；Ca²⁺、Mg²⁺对Sr²⁺在PAN-KTiO上的吸附存在较强的抑制作用；准二级动力学方程能更好地描述PAN-KTiO对Sr²⁺的吸附动力学过程，而Langmuir模型能更好地描述PAN-KTiO对Sr²⁺的吸附等温线；PAN-KTiO对Sr²⁺的吸附过程是以化学吸附为主的单分子层吸附，PAN-KTiO对Sr²⁺的饱和吸附容量可达53.850 mg/g。

Preparation of Polyacrylonitrile-potassium Titanate Spherical Composite Adsorbents and Their Adsorption Properties for Sr2+

Polyacrylonitrile-potassium titanate spherical composite adsorbents (PAN-KTiO) were prepared by supporting KTiO powder on PAN to remove Sr²⁺ from aqueous solution. PAN-KTiO was characterized by SEM, XRD, etc. Sr²⁺ adsorption on PAN-KTiO as a function of contact time, pH, competition ions and initial Sr²⁺ concentration was studied via batch experiments. Furthermore, the adsorptive kinetics and isotherms were analyzed. The results show that the Sr²⁺ adsorption on PAN-KTiO can reach equilibrium after about 24 h. The optimized pH value of solution for Sr²⁺ adsorption on PAN-KTiO is about 6.55. Among the competitive ions, Ca²⁺ and Mg²⁺ significantly hinder Sr²⁺ adsorption on PAN-KTiO. Sr²⁺ adsorption on PAN-KTiO follows a pseudo-second-order kinetic model and is in best agreement with the Langmuir isotherm model, indicating a saturated adsorption capacity of 53.850 mg/g, which also indicates that the Sr²⁺ adsorption on PAN-KTiO is monolayer adsorption and a chemical adsorption process.