磁性材料CuFe_2O_4吸附去除水中土霉素的研究

Adsorptive Removal of Oxytetracycline from Aqueous Solution by Magnetic Material CuFe_2O_4

采用共沉淀法制备了可用磁分离方法进行分离回收的磁性材料CuFe2O4,对其进行了表征及吸附去除土霉素的研究。结果表明,CuFe2O4对土霉素的吸附在24h内达到平衡,吸附动力学过程符合准二级动力学模型;溶液pH值对吸附影响很大,pH=6～7时效果较好,土霉素和CuFe2O4表面的静电相互作用在吸附过程中起着较为重要的作用;等温吸附过程符合Langmuir方程,pH=6时土霉素的最大吸附量达到483.31mg/g;增加溶液离子强度对吸附的抑制作用随土霉素吸附量的增大而变得显著,这与土霉素在CuFe2O4表面形成的络合物形式有关;400℃高温灼烧处理能有效再生磁性材料,材料重复使用性能稳定。

Magnetic material CuFe2O4 which could be separated from the medium by a magnetic technique was prepared using a chemical coprecipitation procedure. The material was characterized and its application for adsorptive removal of oxytetracycline was systematically investigated. The results suggested that the adsorption equilibrium was obtained within 24 h, which was well described by pseudo-second-order kinetics. The adsorption was pH dependent while pH 6-7 favored the adsorption; electrostatic interaction between oxytetracycline and CuFe2O4 played a crucial role in the adsorption process. Langmuir isotherm well described the adsorption isotherm, and the maximum oxytetracycline uptake was estimated to be 483.31 mg/g at pH 6. The inhabitation of adsorption by the increasing ionic strength became significant with the increasing oxytetracycline adsorption, which was related to the type of complex formed between oxytetracycline and the CuFe2O4 surface. CuFe2O, could be easily regenerated through calcinated at 400 ℃, and the adsorption capacity showed stable during several adsorption/regeneration cycles.