Preparation Of Fe₃O₄,MnO₂and Their Application In Removal Of Rhodamine B, Phosphate, Cadmium And Methylene Blue From Water

This article mainly introduces the pollution situation of Phosphate, Rhodamine B, Cadmium, and Methylene blue, and its investigation status at present in the first part.In the second part, we discusses Humic acid (HA) modifying Fe3O4nanoparticles (Fe3O4/HA) and develop it for removal of Rhodamine B from water. Showed the Characterization of Fe3O4/HA and with a saturation magnetization of61.2emu/g, the Fe3O4/HA could be simply recovered from water with magnetic separations at low magnetic field gradients within a few minutes. Sorption of the Rhodamine B to Fe3O4/HA reached equilibrium in less than15min, and agreed well to the Langmuir adsorption model with maximum adsorption capacities161.8mg/g. The Fe3O4/HA was able to remove over98.5%of Rhodamin B in water at optimized pH.In the third part, La-EDTA-Fe3O4was prepared by a chemical co-precipitation method. The magnetic composite was characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). Furthermore, the adsorption properties of La-EDTA-Fe3O4toward phosphate in water were investigated. The uptake rate of phosphate in water by La-EDTA-Fe3O4was3-1000times than that of EDTA-Fe3O4, and reached97.8%at7hr. The adsorption process agreed well with the Freundlich model and kinetics studies showed that the adsorption of phosphate proceeds according to pseudo-second-order adsorption kinetics. The maximum removal rate was achieved at pH6.0-7.0. The La-EDTA-Fe3O4had good adsorption properties and could be separated well from aqueous solution by a permanent magnet. Therefore, this nanomaterial has potential application for the removal of phosphate from large water bodies.In the fourth part, manganese oxide of monosheets was prepared. We investigated the Characterization of manganese oxide, and the adsorption properties on Cadmium and Methylene blue in water. The results shows that the removal rate of Cadmium reached above80%,and agree well to the Langmuir adsorption model with the adsorption capacities above300mg/g. Removal rate of Methylene blue reached above99%, and agree well to the Freundlich model with the adsorption capacities above500mg/g.