Abstract:

Using Ce（NO₃）₃·6H₂O and Zn（NO₃）₂·6H₂O as raw materials，the Ce-Zn composite adsorbent was prepared by co-precipitation method，and was characterized by Fourier transform infrared spectroscopy （FT-IR），X-ray diffraction （XRD） and scanning electron microscopy （SEM）. The adsorption process was fitted by kinetics and thermodynamics. The optimum process conditions for phosphorus removal were determined by orthogonal experiment. The adsorbent was regenerated to study its recycling performance. The results showed that hydrated cerium oxide and zinc oxide particles were formed on the surface of the composite adsorbent，and the surface was rough and porous. The main reason for phosphorus removal was that phosphate ions replaced the metal hydroxyl groups on the surface of the composite adsorbent. The optimum conditions for phosphorus removal were as follows：initial phosphorus concentration of 5 mg/L，pH 4，dosage of 0.07 g，and time of 240 min. The adsorption process conformed to the Freundlich isotherm model and the quasi-second-order kinetic equation. The reaction was spontaneous and endothermic. The adsorbent was recycled by lye for three times，and the phosphorus removal rate was kept above 90%，which proved that the adsorbent could be recycled.

Key words: compound adsorbent, phosphorus removal, adsorption

摘要：

以Ce（NO₃）₃·6H₂O和Zn（NO₃）₂·6H₂O为原料，采用共沉淀法制备Ce-Zn复合吸附剂，利用傅里叶变换红外光谱（FT-IR）、X射线衍射（XRD）、扫描电镜（SEM）对其进行表征，对吸附过程进行动力学和热力学拟合，通过正交实验确定吸附除磷的最佳工艺条件，并对吸附剂进行再生处理，研究其可循环利用性能。结果表明，复合吸附剂表面生成了水合氧化铈和氧化锌颗粒，表面粗糙，呈多孔结构；磷酸盐离子取代复合吸附剂表面的金属羟基是吸附除磷的主要原因。除磷最佳工艺条件：磷初始质量浓度为5 mg/L，pH为4，Ce-Zn复合吸附剂投加量为0.07 g、反应时间为240 min；吸附过程符合Freundlich等温模型和准二级动力学方程，反应自发进行，且为吸热反应；利用碱液对吸附剂进行3次循环脱附再生，对磷的去除率保持在90%以上，证明该吸附剂可以循环使用。

关键词: 复合吸附剂, 除磷, 吸附

CLC Number: 

• X703.1