磁性膨润土的制备及其性能  

PREPARATION AND PROPERTIES OF MAGNETIC BENTONITE

作　　者：王维清[1] 冯启明[1] 董发勤[1] 李虎杰[1] 赵晓东[1] 

机构地区：[1]西南科技大学环境与资源学院,四川绵阳621010

出　　处：《硅酸盐学报》2010年第4期684-688,共5页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金(50804039)资助项目

摘　　要：为实现外加磁场下膨润土处理废水后的快速分离,先以FeCl3·6H2O,FeSO4·7H2O等为主要起始原料,采用共沉淀法制备Fe3O4磁流体,再与膨润土复合制备一系列不同Fe3O4载量(质量分数,下同)的磁性膨润土。采用X射线衍射、Fourier红外吸收光谱、扫描电子显微镜、透射电子显微镜、能谱仪、振动样品磁强计对样品进行表征,研究了Fe3O4载量对磁分离回收率,Cu2+,Zn2+,Cd2+的饱和交换吸附量及去除率的影响。结果表明:Fe3O4微粒附载于膨润土表面而形成磁性集合体,磁性膨润土具有超顺磁性,对Cu2+,Zn2+,Cd2+的饱和交换吸附性能及去除率与原膨润土的相当,但随Fe3O4载量增加而降低。Fe3O4载量为25%时,其饱和磁化强度、剩余磁化强度分别为13.344,0.365A·m2/kg,矫顽力为1.232kA/m,磁分离回收率为90.1%。对浓度为5mmol/L的Cu2+,Zn2+,Cd2+的饱和交换吸附量分别为23.0,21.3,18.9mg/g,去除率分别为27.9%,26.6%,14.3%。In order to effectively separate bentonite from solution in a wastewater treatment process by a magnetic field,a magnetic bentonite with different contents of iron oxide（Fe3O4） was prepared by coprecipation mothod using ferric chloride（FeCl3·6H2O） and ferrous sulphate（FeSO4·7H2O） as primary raw materials.The magnetic bentonite was characterized by X-ray diffraction,Fourier transform infrared spectroscopy,scanning electron microscopy,transmission electron microscopy,energy dispersive spectrometer and vibrating sample magnetometer.The relations among the Fe3O4 content of magnetic bentonite and the magnetic recovery rate,the saturation exchange–adsorption capacity,and the removal rate for Cu^2＋,Zn^2＋,Cd^2＋ ions were also investigated.The results show that Fe3O4 particles coat on the surface of bentonite particles and form the magnetic aggregates.The saturation exchange-adsorption capacity and the removal rate for Cu^2＋,Zn^2＋,Cd^2＋ in magnetic bentonite were similar to those in sole bentonite.For magnetic bentonite with Fe3O4 content of 25%（in mass）,the saturation and remanent magnetizations were 13.344 and 0.365 A·m^2/kg,and the coercive force was 1.232 kA/m.The magnetic recovery rate was 90.1%,the saturation exchange-adsorption capacities for Cu^2＋,Zn^2＋,Cd^2＋ with the concentration of 5 mmol/L were 23.0,21.3,18.9 mg/g,and the corresponding removal rates were 27.9%,26.6%,14.3%,respectively.

关 键 词：磁性膨润土 磁性能 磁分离回收率 饱和交换吸附量 去除率 四氧化三铁 

分 类 号：TQ424.24[化学工程] O482.54[一般工业技术—材料科学与工程]