CoFe2O4-PPy@CS磁性纳米材料制备及吸附研究

用聚吡咯(PPy)和壳聚糖(CS)功能化CoFe2O4,制得CoFe2O4-PPy@CS磁性纳米复合材料。对所得材料的形貌和结构进行表征,并研究了不同环境参数对复合材料吸附Cu^2+、孔雀石绿(MG)和甲基蓝(MB)的影响。结果表明,复合材料吸附Cu^2+和MG(MB)的适宜pH分别为5~7、5~9;随着时间的延长,对Cu^2+、MG、MB的吸附量均逐渐增加,MB的吸附速率要明显快于Cu^2+和MG,并于120 min左右达到吸附平衡,而Cu^2+和MG则需要更长的平衡时间。对Cu^2+的吸附符合Langmuir等温线模型,对MG的吸附符合Freundlich等温线模型,且2种吸附等温线模型均能较好地拟合对MB的吸附过程,最大吸附量分别可达48.3、246.0、233.8 mg/g。三者的吸附动力学均遵循准2级动力学反应模型。

Study on Preparation and Adsorption of CoFe2O4-PPy@CS Magnetic Nanomaterials

CoFe2 O4-PPy@CS magnetic nanocomposites were prepared by modified CoFe2 O4 with polypyrrole(PPy)and chitosan(CS).The morphology and structure of the prepared CoFe2 O4-PPy@CS were characterized.The effects of different environmental parameters on the adsorption of Cu^2+,malachite green(MG)and methyl blue(MB)on composites were investigated.The results showed that the suitable pH for Cu^2+and MG(MB)adsorption by composite was 5~7 and 5~9,respectively.The adsorption capacity of Cu^2+,MG and MB increased gradually with time.The adsorption rate of MB was significantly faster than that of Cu^2+and MG,and the adsorption equilibrium could reach after 120 min,while Cu^2+and MG required longer equilibrium time.The adsorption of Cu^2+was best described by the Langmuir isotherm model,while that of MG followed the Freundlich isotherm,but both of the two adsorption isotherms models could well fit the adsorption process of MB.The maximum adsorption capacity of Cu^2+,MG and MB was 48.3,246.0 and 233.8 mg/g,respectively.The adsorption kinetics of Cu^2+,MG and MB were found to follow the pseudo-second order kinetic equation.