γ-Fe_(2)O_(3)超顺磁纳米颗粒/壳聚糖复合胶体的制备、表征及其对Pb(Ⅱ)的吸附研究

Preparation,characterization and absorption performance to Pb(Ⅱ)of γ-Fe_(2)O_(3) superparamagnetic nanoparticles/chitosan composite colloidal system

超顺磁纳米材料因其具有较好的吸附性能、良好的生物相容性和易固液分离等优点而在重金属的去除研究中备受关注。将壳聚糖与由共沉淀法制备的γ-Fe_(2)O_(3)超顺磁纳米颗粒复合制备γ-Fe_(2)O_(3)超顺磁纳米颗粒/壳聚糖复合胶体体系,利用动态光散射与小角X射线散射技术对胶体粒径及结构进行原位表征,并考察该胶体体系对Pb(Ⅱ)的吸附性能。结果表明:γ-Fe_(2)O_(3)超顺磁纳米颗粒多分散系数较小,与壳聚糖复合后呈软团聚的胶体结构;该胶体体系对Pb(Ⅱ)的吸附动力学符合准二级吸附动力学模型,动力学拟合最大吸附容量为42.9 mg/g,说明该胶体体系对Pb(Ⅱ)具有优异的吸附性能且以化学吸附为主。该胶体体系可为Pb(Ⅱ)污染的水体治理提供实验和技术参考。

Superparamagnetic nanomaterials have attracted increased attention in the field of heavy metal removal due to their good adsorption performance,biocompatibility,and solid-liquid separable.γ-Fe_(2)O_(3) superparamagnetic nanoparticles/chitosan composite colloidal system was prepared by combining chitosan with γ-Fe_(2)O_(3) superparamagnetic nanoparticles as obtained by co-precipitation.The particle size and structure of the colloid system were characterized in situ by dynamic light scattering and small-angle X-ray scattering techniques,and the adsorption performance of the colloid system to Pb(Ⅱ)was further investigated.The results shown that the γ-Fe_(2)O_(3) superparamagnetic nanoparticles were in a low polydispersity coefficient station and a soft-agglomerated colloid system before and after combining with chitosan,respectively.The adsorption kinetics of the colloid system to Pb(Ⅱ)was in agreement well with the quasi-two-stage adsorption kinetic model,and the fitted maximum adsorption capacity was 42.9 mg/g,indicating that the colloidal system has excellent adsorption performance for Pb(Ⅱ)and is mainly chemical adsorption.The colloid system provided an experimental and technical reference for the treatment of Pb(Ⅱ)polluted water bodies.