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以氯化铁(FeCl_3·6H_2O)、氯化锰(MnCl_2·4H_2O)、氯化锌(ZnCl_2)、氯化钴(CoCl_2·6H_2O)、氯化镍(NiCl_2·6H_2O)和氧化石墨烯(GO)为原料,制备了4种铁酸盐与还原氧化石墨烯(RGO)的复合材料(RGO-MFe_2O_4,M=Mn,Zn,Co或Ni),通过扫描电子显微镜、X-射线衍射仪、拉曼光谱仪进行了表征,系统研究了4种材料对亚甲基蓝的吸附。结果发现,RGO-NiFe_2O_4对亚甲基蓝的吸附能力最好,而对吸附起主要作用的是RGO。随着温度升高、染料初始浓度的增加和吸附时间的延长,RGO-NiFe_2O_4吸附量逐渐增大。RGO-NiFe_2O_4对亚甲基蓝的吸附动力学拟合符合伪二级动力学模型。吸附等温线模型拟合结果表明,Langmuir方程可以很好地描述其对亚甲基蓝的吸附。热力学参数ΔG~0在不同温度下均为负值,ΔH~0为正值,ΔS~0为正值说明吸附过程是自发的吸热反应。
Ferric chloride (FeCl 3 · 6H 2 O), manganese chloride (MnCl 2 · 4H 2 O), zinc chloride (ZnCl 2), cobalt chloride (CoCl 2 · 6H 2 O), nickel chloride (NiCl 2 · 6H 2 O) and graphene oxide (GO) (RGO-MFe2O4, M = Mn, Zn, Co or Ni) were prepared from four kinds of ferrite and reduced graphene oxide (RGO) by scanning electron microscopy, X-ray diffraction, The spectrometer was characterized and systematically studied the adsorption of methylene blue by four kinds of materials. The results showed that RGO-NiFe 2 O 4 had the best adsorptive capacity for methylene blue while RGO was the main one for adsorption. With the increase of temperature, initial concentration of dye and adsorption time, the adsorption capacity of RGO-NiFe2O4 increased gradually. Adsorption kinetics of RGO-NiFe 2 O 4 to methylene blue fitted the pseudo-second-order kinetic model. The fitting results of adsorption isotherm model show that Langmuir equation can well describe the adsorption of methylene blue. Thermodynamic parameters ΔG ~ 0 are negative at different temperatures, ΔH ~ 0 is positive, ΔS ~ 0 is positive, indicating that the adsorption process is a spontaneous endothermic reaction.