原位聚合法合成Fe_3O_4/聚丙烯酸纳米粒子及其吸附性能研究

In-situ polymerization for synthesis Fe_3O_4/Polyacrylic acid nanocomposites and study on its adsorption property

采用原位聚合法使丙烯酸单体在共沉淀法制备的Fe3O4纳米粒子表面聚合,获得表面富含羧基官能团的聚丙烯酸(PAA)修饰的Fe3O4纳米粒子(Fe3O4@PAA),采用透射电子显微镜(TEM)、傅里叶变换红外光谱(FT-IR)、振动样品磁强计(VSM)等对其进行表征.同时,研究了其作为吸附剂对水溶液中亚甲基蓝(MB)的吸附性能,考察了水溶液pH值、MB初始浓度、吸附时间以及温度等因素对吸附效果的影响.结果表明:Fe3O4@PAA纳米粒子吸附MB的过程很快,5min内达到平衡.等温吸附过程符合Langmuir模型,T=298K,pH=9.0时,吸附剂的饱和吸附量Qm=0.173mg/mg,吸附常数K=8.167mL/mg.

Magnetic Fe3O4 nanoparticles are prepared by coprecipitation,and corresponding PAA modified magnetite nanoparticles are synthesized by in-situ polymerization with acrylic acid as monomer.The Fe3O4@PAA nanoparticles are characterized by TEM,FT-IR and VSM,etc.Its application to the adsorption of methylene blue（MB） from an aqueous is also investigated.The effect of pH value,the initial concentration of MB,the adsorption time and temperature on MB adsorbed onto Fe3O4@PAA nanoparticles is evaluated.It shows that the adsorption of MB onto Fe3O4@PAA nanoparticles is a very rapid process,reaching the equilibrium within 5 min.The equilibrium data could be fitted well with the Langmuir equation.The maximun adsorption amount of adsorption to MB calculated from the Langmuir equation is 0.173mg / mg and a Langmuir adsorption equilibrium constant of 8.167mL/mg at 298K,pH of 9.