磁性Fe_3O_4/改性焦炭的制备及其对罗丹明B的吸附性能  

Synthesis and rhodamine B adsorption of magnetic Fe_3O_4/modified coke

作　　者：魏晓币 王光华[1] 李文兵[1] 万栋[1] 刘阳[1] 邵秋桐 

机构地区：[1]武汉科技大学化学工程与技术学院,武汉430081

出　　处：《环境化学》2017年第6期1272-1279,共8页Environmental Chemistry

基　　金：湖北省自然科学基金(2014CFB810)资助~~

摘　　要：以焦炭为原料、KOH为活化剂制备改性焦炭,采用原位氧化沉淀法制备纳米Fe_3O_4负载于改性焦炭表面上,制备出磁性复合材料,利用N2等温吸附(BET)、扫描电子显微镜(SEM)、傅里叶交换红外光谱(FTIR)、X射线衍射(XRD)、振动样品磁强计(VSM)等对其进行了表征,并研究了其对罗丹明B的吸附性能,系统考察了吸附动力学、吸附等温线、pH、吸附剂投加量对吸附性能的影响.结果表明,改性焦炭微孔结构发达,利于Fe_3O_4分散负载其表面上.Fe_3O_4/改性焦炭具有良好的磁性能和吸附性能,在2 h内对罗丹明B达到吸附平衡,吸附动力学符合准二级吸附动力学方程,等温吸附数据符合Langmuir模型,吸附是自发行为且为吸热反应.吸附剂在较宽的pH范围内有较高的吸附量,罗丹明B去除率可达98.32%.Modified coke was prepared from coke by KOH activation. Nano-sized Fe3O4 were loaded onto the surface of the modified coke by in-situ oxidation precipitation,and the magnetic composite material was obtained. The magnetic composite material were characterized by nitrogen adsorption isotherms（BET）,scanning electron microscopy（SEM）,Fourier transformed infrared spectroscopy（FTIR）,X-ray powder diffraction（XRD） and vibrating sample magnetometer（VSM）. Adsorption kinetics,adsorption isotherm,pH as well as the effect of adsorbent dosage on the removal efficiency of rhodamine B（Rh B） were systematically investigated. The results show that a pore structure was developed,on the modified coke which was conducive to the Fe3O4 dispersion on its surface.Fe3O4/modified coke possessed excellent magnetic properties and adsorption capacity. The adsorption of RhB reached equilibrium within 2 h,and the sorption processes conformed to the pseudo-second-order kinetics equation. The sorption isotherm fit to the Langmuir model,and the adsorption was spontaneous and endothermic. The adsorption capacity of the adsorbent was high in a wide pH range,and the removal rate of RhB reached 98.32%.

关 键 词：改性焦炭 Fe3O4/改性焦炭 吸附 磁性 罗丹明B 

分 类 号：O647.3[理学—物理化学] X791[理学—化学]