| 摘要 |
<p>The raw materials based on iron oxides, which contain foreign matter of zinc, lead, chromium, silica and aluminium, are thermally processed in a mixture with alkaline hydroxide in a mass ratio of 1:1 to 1:10 at a temperature from 300 degrees C to 1,000 degrees C for 1 to 20 hours. The product is then leached with water.</p> |
