Magnetic Mesoporous Carbon Modified By Aminated Hollow Magnetic Nanospheres:Synthesis,Characteristic And Sorption

This article composited the ordered mesoporous carbon and hollow iron oxide nanometer microspheres after modification,and characterized the composite materials in detail.Then the materials were used for the adsorption of methylene blue test.The ordered mesoporous carbon presented the uniform mesopores,larger surface area,developed pore structure,good thermal and chamical stability and well adsorption capacity,which might be resulted in more anchoring sites for a variety of applications such as catalysts supporter,super-capacitor,medicine release involving the practical application of large hydrophobic molecules(ibuprofen,vitamins,dyes).Many researchers through the modification of ordered mesoporous carbon or introduce of impurity atoms into the matrix to improve the physical and chemical properties for higher adsorption capacity and catalytic degradation ability which makes the mesoporous carbon beneficial to the environmental and energy application.For example,nitric acid oxidation can introduce carboxyl groups into the carbon material and change its surface hydrophobic/hydrophilic balance.Some researchers incorporated some metallic elements(Pd,Zn,Co,Fe,Zr etc.)into ordered mesoporous carbon during the preparation or via post-synthetic methods which had led to high performance such as adsorption,catalyst and magnetism.Recent years,hierarchically structured magnetic iron oxide materials especially hollow iron nanospheres had been paid extensive attentions after modified as it possesses magnetic,non-toxic,hydrophilic,stable chemical performance,easy prepared and recycling.The hollow structure nano-material enclosed a vacant volume at their centers and presented shell-like ordered independent nanoparticles outside.The structure provided a high surface area,high polarity,large interior space,quantum sizes,low density,thermal and chemical stability and high permeability.As a consequence,these properties provided a higher removal capacity for heavy metal ions and dyes molecules.It might be an alternative choice to combine ordered mesoporous carbon with hollow iron nanospheres to affect the surface charge each other and improve separation capacity.In this paper,Magnetic mesoporous carbon w:ith particular morphology was successfully fabricated by immobilizing uniform aminated hollow magnetic nanospheres(AHMNs)into oxidized mesoporous carbon(OMC)matrix with different mass ratio.The morphology and surface properties were studied using SEM,BET,XRD,FTIR,XPS and VSM.Batch experiments were carried out to study the sorption behavior of methylene blue(MB)by AHMOC-Ys,indicating that a good adsorption capacity of cation dye could be obtained at a mild condition(at pH = 8 compared with pH = 11)which was sustained by point of zero charge(pHpzc,).The conclusion revealed that AHMOC-2:1 had advantages in adsorption capacity and separation feasibility compared with other materials.The characterizations of adsorption behavior revealed that isotherm and kinetics synthesis were well-fitted respectively by pseudo-second-order model and Freundlich isotherm model.The rate-limiting step was mainly involved film diffusion and intra-particle diffusion for the whole reaction.Thermodynamic analysis indicated that the adsorption reaction was an endothermic and spontaneous process.