摘要 |
The present invention relates to the selective removal of mercury from an aqueous feed solution, wherein the feed solution comprises mercury in addition to one or more precious metals. In particular, the present invention is useful for removal of mercury from processing waters produced during precious metal mining processes. The process comprises contacting the aqueous feed solution with a solid sorbent material comprising thiol and/or thiolate functional groups, wherein (i) the aqueous feed solution comprises at least 10 ppm of free cyanide ions; and/or (ii) the sorbent material is contacted with an aqueous cyanide solution after contact with the aqueous feed solution to selectively desorb precious metal from the sorbent material. Suitably, the precious metal is gold and/or silver. The thiol and/or thiolate functional groups may be immobilised on a solid support. The use of a sorbent material comprising thiol and/or thiolate functional groups for selectively removing mercury from an aqueous feed solution is also claimed. |