摘要
以球磨后的粉煤灰磁珠(MS)颗粒为磁核,通过溶胶凝胶法和反相微乳液法依次包覆SiO_2和壳聚糖(CS),制备了MS@SiO_2@CS磁性微球。利用扫描电镜及能量色散谱仪、热重分析仪、红外光谱仪、X射线衍射仪、振动样品磁强计对所得样品的结构和磁性进行了系统表征。结果表明,磁珠颗粒表面实现了逐层包覆,较均匀的分散于壳聚糖基体中,MS@SiO_2@CS微球的比饱和磁化强度可达7.04 emu·g^(-1)。Cu^(2+)离子吸附实验表明,所得磁性壳聚糖微球对Cu^(2+)具有良好的吸附能力,最大吸附量可达11.08 mg·g^(-1);而且可通过磁选法高效固液分离。吸附动力学研究表明,MS@SiO_2@CS微球对Cu^(2+)离子的吸附符合准二级动力学模型,以化学吸附为主。
MS@SiO2@CS magnetic micron spheres were fabricated by successively coating the ball-milled coal fly ash magneticsphere （MS） particles with SiO2 and chitosan （CS） through a sol-gel and an inverse microemulsion method, respectively. The structures and properties were carefully characterized by scanning electron microscopy （SEM）, energy dispersive spectroscopy （EDS）, thermogravimetric analysis （TGA）, Fourier transform infrared spectroscopy（FTIR）, X-ray diffraction（XRD）, and vibrating sample magnetometer（VSM）. The results showed that the MS particles were coated layer by layer of SiO2 and CS, respectively, and relative evenly distributed in the CS substrate. Since MSs are magnetic, the MS@SiO2@CS samples also show relatively strong magnetism with a specific saturation magnetization of 7.04 emu.g-＇. Adsorption experiments indicated that the magnetic composite micronspheres showed the good adsorption capability for Cu^2＋ ions, and the adsorption capacity was up to 11.08 mg·g^-1. In addition, after Cu^2＋ adsorption, the adsorbents could be separated effectively from water by magnetic separation. According to the adsorption kinetics simulation, the Cu〉 adsorption of MS@SiO2@CS corresponds to pseudo second order kinetics, which implies a dominant chemical adsorption.
作者
李建军
鲍旭
吴先锋
Islam Nazrul
刘银
乔尚元
余臻伟
朱金波
LI Jian-Jun BAO Xu WU Xian-Feng Islam Nazrul LIU Yin QIAO Shang-Yuan YU Zhen-Wei ZHU Jin-Bo(Department of Materials Science and Engineering, Anhui University of Scienee and Technology, Huainan, Anhui 232001, China Institute for Superconducting and Electronic Materials, University of Wollongong, Wollongong NSW 2500, Australia)
出处
《无机化学学报》
SCIE
CAS
CSCD
北大核心
2017年第3期383-388,共6页
Chinese Journal of Inorganic Chemistry
基金
国家自然科学基金(No.51374015)
教育部博士点专项基金(No.20133415120004)
安徽省高校自然科学研究重点研究项目(No.KJ2016A189)资助
关键词
粉煤灰磁珠
磁性壳聚糖
吸附
重金属离子
磁分离
fly ash magneticspheres
magnetic chitosan
adsorption
heavy metal ions
magnetic separation
