| 摘要 |
<p>A process is provided for preparing a preferred ferric sulfate solution. The product of the process is particularly suited for use in water treatment and purification. According to the process, iron oxides or iron, are dissolved in sulfuric acid to form ferrous sulfate. In a first step of oxidation, the ferrous sulfate is partially oxidized to ferric sulfate in the presence of dissolved oxygen. In a second stage of oxidation, remaining ferrous sulfate is oxidized to ferric sulfate by the action of a non-molecular oxygen oxidizing agent such as hydrogen peroxide. During both stages of oxidation, a catalyst such as copper sulfate or copper ammonium sulfate may be used. Careful control of added sulfuric acid is maintained, to avoid excess or free sulfuric acid in the reaction product. The final reaction product is generally characterized by having: between about 10% and 12% iron by weight; substantially all iron present in the ferric form; and, by having less than 0.5% free or excess acid, by weight.</p> |
