摘要 |
<p>An aqueous solution, for example, effluent from an off-gas scrubber, is treated to remove metal and metalloid ions by in situ precipitation of ferrous ions by the addition thereto of a ferrous ion-containing solution, salt or other such ferrous ion-containing source and a hydroxil-yielding base in the presence of the metals and metalloids. The reaction conditions include a temperature of at least about 60 °C, and a pH of from about 6 to about 10.</p> |