Abstract
Ultra fine magnetite particles, with the mean particle size of 75Å, were produced at pH 12 after adjusting the mole ratio of Fe2+/Fe3+ to 0.5 by partial oxidation of the waste pickling liquor of steel. After double adsorption of oleic acid ion and dodecyl benzene sulfonate (D. B. S) ion on the surface of magnetite particles, magnetite hydrophilic magnetic fluid was produced by dispersing the magnetite particles in ethylene glycol solution. The ethylene glycol based magnetic fluid enhanced the capability of oil seals. The life span of the sealing apparatus composed of mild steel components was remarkably extended due to the high corrosion resistance of ethylene glycol.
