| 摘要 |
<p>The invention provides a process for reclaiming chromium from roasted chromium ash containing chromium in substantially completely the hexavalent state, comprising: mixing the ash with sulfuric acid and water to form an acid-ash slurry; adding a reducing agent to the slurry to convert the hexavalent chromium to the trivalent state; filtering out an extract solution; water-washing the residue; and applying the water-wash to use as one of waste treatment processing, a component of a pickling agent, and a re-cycled solution; the extract solution providing reclaimed chromium. This procedure not only produces an appropriate chrome tanning liquor with specific tanning properties, but also results in an inert residue which is safely disposable, non-polluting, and even useful as a filler material in the leather manufacturing process or as a form of clay.</p> |
