METHOD FOR THE REMOVAL OF METALS FROM SOLUTION BY MEANS OF ACTIVATED SILICA

摘要

The surprising ability of the polysilicate microgels commonly known as "activated silica" to adsorb and to release heavy metals selectively as a function of pH is used in a novel method for separating metals from dilute aqueous solution by means of selective precipitation with and recovery from an activated silica absorbent, selected changes to the pH. The process is particularly intended for the economic purification of contaminated waste streams to recover valuable but toxic heavy metals from such effluents at a lower cost than hitherto possible, using an activated silica substrate which may be regenerated by alkali treatment.