News

French technology recovers gold from water

Posted on 31 Oct 2012

magpie.jpgMagpie Polymers has an innovative and patented filtration technology for the selective removal of transition metals from industrial waste or process water. Its technology gives a high-performance and simple to apply solution to the increasing problem of metals in water. It is best suited for toxic metal removal and recovery of precious metal. The company, a spin-off from the French Institute Ecole Polytechnique, produces different patented polymers to capture a large number of metals including cobalt, cadmium, gold or even uranium, leaving less than a mg/m3 of metal in water. Magpie also recovers the captured metals, specifically the increasingly scarce and valuable metals.Magpie’s Polymers fix metals in a standard filtration process, using co-ordination chemistry. Selective bonds are formed between the metals and the polymer beads. This is very different from ion-exchange chemistry, commonly used in water treatment, giving Magpie, it says, “improved performance and improved selectivity:

  • Low residual concentration (1 µg/l after filtration)
  • Unequalled selectivity
  • Efficient in hard and salty water
  • Broad pH range (below 1 and up to 12).”

Magpie Polymers produces different types of filtration beads, sized between 0.5 and 1 mm. They are used in standard filtration columns identical to ion-exchange filtration systems. These filtration products can be purchased in easy to use evaluation kits, in 25 kg bags or  in ready-to-use columns.