摘要
采用非原位共沉法简易合成了β-环糊精壳聚糖磁性纳米颗粒(β-CD@CS MNPs),对其性质进行了系统表征,并对其富里酸吸附行为进行了初步研究.扫描电镜(SEM)和透射电镜(TEM)结果表明β-CD@CS MNPs的纳米尺寸为(52±3)nm,且比较均一,X-射线衍射仪(XRD)表征结果表明β-CD@CS MNP具有尖晶石的结构,振动样品磁强计测得饱和磁化强度为62 emu·g^(-1),具有超顺磁性.同时,探讨pH、吸附剂含量、初始浓度、温度以及吸附时间对吸附性能的影响,吸附实验结果显示,β-CD@CS MNPs对富里酸的实际吸附量为51.35 mg·g^(-1)(25℃,pH=7.0±0.1),在600 min内达到吸附平衡,吸附过程为吸热反应,其中,β-CD@CS MNPs对富里酸的吸附行为符合Langmuir等温线模型和拟二级动力学模型,吸附机理可能涉及静电作用、氢键结合、疏水作用以及因β-CD的疏水空腔与有机污染物的主客体作用而具有的包合作用.
β-cyclodextrin chitosan magnetic nanoparticles（ β-CD @ CS MNPs） were facilely synthesized by an ex situ co-precipitation method. The adsorbent was characterized using mutiple techniques and its performance for fulvic acid（ FA） removal from solution was investigated. The SEM and TEM image indicated that the shape of β-CD@ CS MNPs was in uniform with size of（ 52± 3） nm. X-ray powder diffraction（ XRD） analysis showed that the magnetic phase in β-CD@ CS MNPs was spinel magnetite. The absorbent has super-paramagnetic and saturation magnetization of 62 emu·g^-1. Meanwhile,the effect of pH,adsorbent content,temperature,initial concentration and adsorption time on adsorption capacity was studied. The results showed that the practical adsorption capacity for FA was 51. 35 mg·g^-1at pH 7. 0 ± 0. 1 under 25 ℃,and the adsorption equilibrium was obtained in 600 min. The adsorption process was endothermic. Furthermore,the experimental data showed that the adsorption behavior of β-CD@ CS MNPs for FA was well fitted by Langmuir isotherm model and pseudo-second-order model. Adsorption mechanism of FA may involve electrostatic interaction,hydrogen bonding and hydrophobic interaction,as well as inclusion interaction which contributed to the host-vip interactions between β-CD molecules and organic contaminant.
作者
赵静
王田天
刘泽珺
马福臻
周少奇
ZHAO Jing WANG Tiantian LIU Zejun MA Fuzhen ZHOU Shaoqi(School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510640 School of Environment and Energy, South China University of Technology, Guangzhou 510006 State Key Laboratory of Subtropical Building Science, South China University of Technology, Guangzhou 510640)
出处
《环境科学学报》
CAS
CSCD
北大核心
2017年第3期977-987,共11页
Acta Scientiae Circumstantiae
基金
国家重点研发计划(No.2016YFC0400708)~~
关键词
Β-环糊精
壳聚糖
磁性纳米粒子
吸附
富里酸
β-cyclodextrin
chitosan
magnetic nanoparticles
adsorption
fulvic acid
