Study on preparation and effect of nanosized Fe₃O₄ magnetic organic fluids

The Fe₃O₄ magnetic water fluids was prepared with liquid-phase coprecipitation. By using oleic acid to treat the the surface of Fe₃O₄ and extract the Fe₃O₄ from water, nanosized Fe₃O₄ nanoparticle coated by oleic acid was gotten, by detracting them in organic fluids, nanosized Fe₃O₄ magnetic organic fluids was gotten. The phase structure of the particles and the average size and size distribution were determined by X-ray diffraction (XRD) and granularity analysis instrument, the characterization was determined by FT-IR and HRTEM. Results show that the average size of the prepared cube crystal nano Fe₃O₄ is 16.3 nm; the strong absorptivity at 1593, 1736 and 2926 cm^-1 in FT-IR spectra shows that Fe₃O₄ nanoparticle is coated by oleic acid; The prepared Fe₃O₄ nanoparticle coated by oleic acid can be detracted steadily in organic fluids.