Preparation And Properties Of Iron-based Oxides

In this thesis,Ti-Fe alloys and Zr-Fe alloys with atomic ratios of 1:3 were prepared by vacuum melting method,iron-based oxide powders have been achieved directly by anodizing the metal Fe,Ti-Fe alloy and Zr-Fe alloy in inorganic electrolytes.Fe₂O₃powders and composite oxide powders made up of titanium iron atoms and zirconium iron atoms?atomic ratio 1:3?were prepared by chemical coprecipitation process.SEM,XRD,UV-vis,FTIR,XPS and VSM were carried out to show the morphologies,structures,magnetic,absorption properties and heat regeneration properties of the samples,which were prepared by anodization process and chemical coprecipitation process.1.Zr-Fe alloys and Ti-Fe alloys with atomic ratio of 1:3 were prepared by vacuum melting method,then iron-based oxide powders were prepared in inorganic solution containing NH₄Cl and?NH₄?₂SO₄ with volume ratio of 2:1 by anodization process,and the best morphology of the powders was obtained through controlling the reaction temperature,voltage and other conditions.Fe₂O₃ powders and composite oxide powders made up of titanium iron atoms and zirconium iron atoms?atomic ratio 1:3?were prepared by chemical coprecipitation process,and then their morphology characteristics were studied by making a comparison with those of powders prepared by anodization process.2.The phase compositions of the samples prepared by the above two process were studied.The newly prepared samples are mostly amorphous structure,with the increasing of annealing temperature,the crystallization degree of the samples was increased significantly.Phase composition and grain size of the samples prepared by the two process has little differences,but the crystallization temperature of the samples prepared by chemical coprecipitation was significantly higher than that of the samples prepared by anodization process.3.The adsorption properties of iron-based oxide powders for alizarin red,neutral red,methyl blue,methyl orange,phenolphthalein and phenol were investigated.Results show that the adsorption properties were closely related to the samples composition,preparation method,calcination temperature and the type of organics.It was the best for the alizarin red that the adsorption properties of the titanium iron composite oxide powders prepared by chemical coprecipitation process annealed at 350?,and the adsorption rate is as high as94.3%,the adsorption capacity is 47.15 mg/g.4.The heat regeneration properties of Fe₂O₃ powders and titanium iron composite oxide powders after adsorbing dyes were studied and the results demonstrate that the samples could regenerate completely by calcining at 500?for 2h,with the increasing of heat regeneration experiments,the adsorption properties of the samples for dyes gradually weakened,then stabilized.5.Preparation method and ingredients have significant effects on the magnetic properties of the samples,compared with the Fe2O3 powders,the coercivity and remanence of composite oxide powders decreased;Preparation method,Ti doping and Zr doping have a certain effects on the optical absorption properties and optical bandgap of the samples.