| 摘要 |
PURPOSE:To obtain homogeneous needlelike goethite by adding alkali to a ferrous salt soln., adjusting the ratio of anions to ferrous ions to <=1, and carrying out oxidation with sodium chlorate or potassium chlorate. CONSTITUTION:Alkali is added to a ferrous salt soln. such as a ferrous sulfate soln. to precipitate ferrous hydroxide at >=11pH, and the ratio of anions to ferrous ions is adjusted to <=1. At this time, the setting time of ferrous hydroxide is controlled to 2-16hr. Sodium chlorate or potassium chlorate is then added to manufacture needlelike goethite by oxidation at <=80 deg.C. |
