| 摘要 |
PURPOSE:To industrially produce an acicular goethite particle powder consisting of fine particles with the aspect ratio (major axis/minor axis) controlled to >=10. CONSTITUTION:An aq. ferrous salt soln. is allowed to react with an aq. alkali in an amt. less than the equivalent to the Fe<2+> in the soln. to obtain a ferrous slat reacting soln. contg. a ferrous hydroxide colloid or the colloid of the iron- contg. precipitate. An oxygen-contg. gas is passed through the soln. which is oxidized to obtain a ferrous salt reacting soln. having <=30% oxidation degree in the soln. and contg. a mixture of the acicular goethite nucleus particle resulting from green rust and the green rust. A goethite fine-particle powder is added to the soln. to form an acicular goethite nucleus particle which is then grown, and an acicular goethite particle powder is obtained. |
