磁性聚合物吸附树脂的制备及其重金属离子吸附性能研究

发布时间：2018-03-25 03:19

本文选题：重金属离子　切入点：磁性纳米粒子　出处：《成都理工大学》2017年硕士论文

【摘要】：本文采用改良共沉淀法制备磁性纳米粒子,然后用硅烷偶联剂KH570对磁性纳米粒子进行表面修饰,并将KH570改性磁性纳米粒子与功能性单体和聚乙烯基吡咯烷酮进行接枝共聚制备具有半互穿网络结构的磁性聚合物重金属离子吸附树脂,考察了聚合反应参数和吸附条件对磁性聚合物吸附树脂重金属离子吸附性能的影响,采用多种现代表征手段对磁性聚合物吸附树脂结构进行了表征,研究磁性聚合物吸附树脂的重金属离子吸附动力学和吸附热力学,考察磁性聚合物染料吸附树脂的解吸和循环再生利用性能,并初步探究磁性聚合物重金属离子的吸附机理,主要研究结果如下:1、SEM表征显示磁性聚合物具有三维网络结构,树脂表面不平整、具有大量的网孔和沟壑;VSM结果表明与磁性Fe_3O_4纳米粒子相比,KH570改性磁性纳米粒子和磁性聚合物吸附树脂的磁化强度值均有所降低,但依旧具有很高的磁性,表现为超顺磁性;磁性纳米粒子分散液和KH570改性磁性纳米粒子分散液均具有明显的丁达尔现象和快速的磁响应性。2.XRD表征表明经过硅烷偶联剂表面修饰和接枝聚合的磁性Fe_3O_4纳米粒子的晶型结构均未发生改变;FTIR表明KH570成功对磁性Fe_3O_4纳米粒子进行表面修饰,制备的磁性聚合物吸附树脂具有目标结构,TGA表明磁性聚合物吸附树脂具有较高的磁含量和热稳定性;。3、当引发剂用量为0.8%、交联剂用量为0.2%、丙烯酸/丙烯酰胺质量比为60:40、丙烯酸中和度为70%、PVP含量为12%、KH570改性Fe_3O_4磁性纳米粒子含量为20%时,制备的磁性聚合物吸附树脂对Cu~(2+)吸附容量分别达到最大值。4、磁性聚合物吸附树脂重金属离子吸附容量随吸附时间呈现先快速增加后增幅趋缓趋势,60 min基本达到吸附平衡;随着pH的增大,重金属离子吸附容量先增后降;随着重金属离子初始浓度的增加,磁性聚合物吸附树脂重金属离子吸附容量呈先快速增大后趋缓的趋势,磁性聚合物吸附树脂重金属离子的吸附容量随温度的升高而降低。5、磁性聚合物吸附树脂重金属离子Cu~(2+)、Pb~(2+)、Cd~(2+)吸附过程符合准二级动力学方程和Langmuir等温吸附模型。6、磁性聚合物吸附树脂对重金属离子解吸速率较快,解吸60 min达到解吸平衡,磁性聚合物吸附树脂Cu~(2+)、Pb~(2+)、Cd~(2+)的解吸率分别达到了99%、98%和95%以上,表明磁性聚合物吸附树脂具有较好的解吸性能。经过5次循环使用,磁性聚合物吸附树脂重金属离子Cu~(2+)、Cd~(2+)、Pb~(2+)吸附容量分别达123.2 mg/g、90.2 mg/g和333.5 mg/g,分别达到重金属离子第一次吸附容量的75.6%、74.1%和71%,表明磁性聚合物吸附树脂具有较好的循环再生利用性能。
[Abstract]:In this paper, magnetic nanoparticles were prepared by modified coprecipitation method, and then modified by silane coupling agent KH570. KH570 modified magnetic nanoparticles were grafted with functional monomer and polyvinylpyrrolidone to prepare magnetic polymer heavy metal ion adsorption resin with semi-interpenetrating network structure. The effects of polymerization parameters and adsorption conditions on the adsorption properties of heavy metal ions of magnetic polymer adsorption resin were investigated. The structure of magnetic polymer adsorbed resin was characterized by various modern characterization methods. The adsorption kinetics and thermodynamics of heavy metal ions of magnetic polymer adsorption resin were studied. The desorption and recycling properties of magnetic polymer dye adsorption resin were investigated, and the adsorption mechanism of magnetic polymer heavy metal ion was preliminarily studied. The main results are as follows: SEM characterization shows that the magnetic polymer has a three-dimensional network structure, and the surface of the resin is uneven. Compared with the magnetic Fe_3O_4 nanoparticles, the magnetization of the modified magnetic nanoparticles and the adsorbed resin of the magnetic polymer is decreased, but the magnetic properties are still very high, showing superparamagnetism, compared with the magnetic Fe_3O_4 nanoparticles with a large number of meshes and grooves. Both magnetic nanoparticles dispersion and KH570 modified magnetic nanoparticles dispersion have obvious Dundar phenomenon and fast magnetic response. 2. XRD characterization shows that magnetic Fe_3O_4 nanoparticles modified by silane coupling agent and grafted polymerized are magnetic Fe_3O_4 nanoparticles. FTIR showed that KH570 successfully modified the surface of magnetic Fe_3O_4 nanoparticles. The magnetic polymer adsorption resin prepared has the target structure. TGA shows that the magnetic polymer adsorption resin has high magnetic content and thermal stability. When the initiator dosage is 0.8, the crosslinking agent dosage is 0.2, the mass ratio of acrylic acid to acrylamide is high. When the neutralization degree of acrylic acid is 70 and the content of PVP is 12 and the content of magnetic nanoparticles modified by KH 570 is 20, The adsorption capacity of magnetic polymer adsorbed resin on Cu~(2 reached the maximum value of .4, and the adsorption capacity of heavy metal ions of magnetic polymer adsorption resin increased rapidly first and then increased slowly with the adsorption time. The adsorption equilibrium was achieved for 60 min. With the increase of pH, the adsorption capacity of heavy metal ions first increased and then decreased, and with the increase of initial concentration of heavy metal ions, the adsorption capacity of heavy metal ions of magnetic polymer adsorbed resin increased rapidly and then slowed down. The adsorption capacity of heavy metal ions of magnetic polymer adsorbed resin decreased with the increase of temperature. The adsorption process of magnetic polymer adsorbed resin heavy metal ion Cu~(2 was in accordance with quasi second order kinetic equation and Langmuir isotherm adsorption model. The desorption rate of heavy metal ions by magnetic polymer adsorption resin is faster. The desorption equilibrium was achieved at 60 min, and the desorption rate of magnetic polymer adsorption resin (Cu~(2) was over 990.98% and 95%, respectively, which indicated that the adsorption resin had better desorption performance. The adsorption capacity of heavy metal ion Cu~(2 / CD ~ (2 +) is 123.2 mg / g ~ (90.2 mg/g) and 333.5 mg / g, respectively, which is 75.6% and 71.1% of the first adsorption capacity of heavy metal ions, respectively, indicating that the magnetic polymer adsorption resin has better recycling and recycling properties.
【学位授予单位】：成都理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O647.3;TQ324.8

【参考文献】