摘要
以共沉淀法制备纳米Fe3O4,通过分散聚合法制备了磁性聚(苯乙烯-甲基丙烯酸)(Fe3O4@P(St-MMA))微球,采用光学显微镜、红外光谱、样品磁力振荡计和X射线衍射(XRD)对磁性微球进行了表征。考察了复合磁性微球在不同的p H、离子强度和吸附时间等条件下对其吸附性能的影响,运用吸附动力学和吸附等温线研究了磁性微球对亚甲基蓝的表面吸附机理。结果表明,制备的磁性微球粒径在100~200μm之间,表面含有羧基,饱和磁化强度为9.44 emu/g,在外加磁场的作用下能够快速分离出来。亚甲基蓝的吸附符合准二级动力学模型,在100 min内基本达到吸附平衡;25℃下,最大吸附量高达144.9 mg/g,且吸附随着p H值的升高而增加,当p H>7时,吸附量基本不变;随着离子强度增加,吸附量逐渐下降;Langmuir等温线能比较好地拟合磁性微球对溶液中亚甲基蓝的吸附。
Fe3O4were made by coprecipitation method. The magnetic Fe3O4/ poly( styrene-methacrylic acid)( Fe3O4/ poly( St-MAA)) microbeads were prepared by dispersion polymerization in the presence of Fe3O4 nanoparticles. The obtained magnetic microbeads were characterized by optical microphotographs,fourizer transform infrared spectroscopy( FT-IR),vibrating-sample magnetometer( VSM) and X-ray diffraction( XRD). The effects of methylene blue( MB) adsorption were studied in different p H,adsorption times and ionic strength on the adsorption process. Adsorption mechanism of MB on the surface of magnetic microbeads was explored by the methods of adsorption kinetics and the adsorption isotherm. The results indicated that the diameter of magnetic microbeads was 100 ~ 200 μm. FT-IR indicated that there were abundant functional groups —COOH on the surfaces of the magnetic microbeads. The saturation magnetization of magnetic microbeads adsorbent was 9. 44 emu /g,which was sufficient to separate from aqueous solution. The adsorption processes of MB coincided with the pseudo-second-order kinetic model and the adsorption equilibrium was reached within 100 min. Under 25℃,the saturated adsorption capacity attained 144. 9 mg / g. Adsorption quantity increased gradually with increasing p H value. When the solution p H value was more than 7,the absorption capacity of magnetic microbeads basically kept constant. The adsorption capacity of magnetic microbeads decreased with increasing ionic strength. The isotherm data were well fitted by Langmuir model.
出处
《环境工程学报》
CAS
CSCD
北大核心
2015年第3期1214-1220,共7页
Chinese Journal of Environmental Engineering
基金
内蒙古自治区高等学校科学研究项目(NJZC14273)
内蒙古自然科学基金面上项目(2014MS0215)
关键词
分散聚合
磁性微球
吸附
亚甲基蓝
dispersion polymerization
magnetic microbeads
adsorption
methylene blue
