Fe_3O_4/SDS磁性纳米颗粒吸附水体中的Cd^(2+)和Zn^(2+)

SDS coated Fe_3O_4 magnetic nanoparticles for adsorption of Cd^(2+) and Zn^(2+) in aqueous solution

一种新型纳米固相萃取吸附剂,由阴离子表面活性剂十二烷基磺酸钠(SDS)包裹在Fe3O4磁性纳米颗粒表面形成,用于吸附水溶液中的重金属离子。研究了吸附过程的主要影响因素(如SDS浓度、溶液pH等)以及解吸过程的最佳条件,并对其机理进行了初步的探讨。研究结果表明,共沉淀法制备的Fe3O4颗粒粒径分布均匀,平均粒径约为54 nm;SDS浓度为300 mg/L时,Fe3O4/SDS磁性纳米颗粒吸附Cd2+和Zn2+的能力最强;在一定浓度范围内,Fe3O4/SDS体系对Cd2+和Zn2+的吸附平衡数据符合Langmuir吸附等温方程,饱和吸附量分别为22.42 mg/g和13.95 mg/g。最终结果表明,Fe3O4/SDS磁性纳米颗粒具有较强磁分离能力和较好的吸附效果。

A novel nanosize solidphase adsorbent,i.e.Fe3O4 magnetic nanoparticles coated by SDS,could be used to remove heavy metal from aqueous solution.The main factors affecting the adsorption process,such as SDS concentration and the solution pH,and the optimal condition for desorption,were investigated.The mean diameter of Fe3O4 nanoparticles prepared by co-precipitating method was about 54 nm.The adsorbent had the highest adsorption capacity when the concentration of SDS was 300 mg/L.The adsorption of Cd2＋ and Zn2＋ agreed well to Langmuir adsorption model with the maximum adsorption capacities of 22.42 mg/g and 13.95 mg/g,respectively.It had strong magnetic separability and great adsorption capacity.