Preparation And Properties Of Protein Fiber Iron Complexes For Catalytic Degradation Of Azo Dyes

In this paper,three kinds of wool fibers with different diameters and flake structures were selected to coordinate with Fe³⁺ ions,and then three wool fiber Fe complexes were obtained.The effects of some factors on the coordination reaction between wool fibers and Fe³⁺ ions were investigated,especially the wool fiber diameter and flake structure.The molecular structures and surface morphologies of wool fiber Fe complexes were characterized by scanning electron microscope?SEM?,Fourier transform infrared spectrometer?FTIR?,X-ray diffractometer?XRD?,X-ray photoelectron spectroscopy?XPS?and diffuse reflectance UV-Vis spectra?DRS?analyses.Then,the resulting three kinds of wool fiber Fe complexes were used as heterogeneous Fenton reaction catalysts for the oxidative degradation of azo dye reactive red 195,respectively.The effects of the concentration of Fe³⁺ ions and H2O2,the inorganic salts and the intensities of the irradiation on the catalytic activity were studied.And the roles of the wool fiber diameter and flake structure on the catalytic activity of the complexes were also evaluated.Finally,different protein fibers,silk fiber and wool fiber,were coordinated with Fe³⁺ ions to prepare fiber Fe complexes and their catalytic degradation performances were compared.The results showed that all the three kinds of wool fibers with different diameters and flake structures could react with Fe³⁺ ions to form fiber Fe complexes.Increasing the concentration of Fe³⁺ ions or the reaction temperature could give rise to higher Fe content of complexes.Under the same reaction conditions,the wool fibers with smaller flake thickness were more likely to coordinate with Fe³⁺ ions.Three wool tfiber Fe complexes showed high catalytic activity for the degradation of azo dyes.Increasing Fe content loaded on complexes would significantly improve their catalytic activity,especially under visible irradiation.Under the same reaction conditions,the smaller diameter of the wool fiber Fe complex showed better catalytic performance.The coordination ability of dyed wool fibers with Fe³⁺ ions was decreased,but the complexes still had good catalytic performance.Although the silk fiber is more difficult to coordinate with Fe³⁺ ions,silk fiber Fe complexes showed more excellent photocatalytic degradation performance than wool fiber Fe complexes under the same conditions.