摘要 |
<p>Extraction agents for the extraction of copper, zinc, uranium and nickel, or any of these, from aqueous solutions containing same, comprise a macroporous polymer supporting a specific extractant for such metal, the polymer being rendered hydrophilic by the method of impregnation or by attachment thereon of suitable functional groups, or by attaching such functional groups to the extraction agent, or by coabsorbing on said polymer an agent adapted to render the polymer hydrophilic. Such extraction agents may be produced by impregnating a macroporous polystyrene with a specific metal extraction agent in the presence of a diluent for the extraction agent, removing external diluent, contacting the product with a solution of the metal to be extracted, and removing the metal from the extraction agent by a suitable eluting agent. Alternatively, a macroporous polymer may be impregnated with a selective extraction agent complexed with the metal to be extracted in the presence of a diluent, the external diluent removed and the metal eluted with a suitable eluent. Furthermore, macroporous polymers containing finely dispersed metal powders may be prepared, which polymers can be used as catalyst in organic synthesis.</p> |