LEWATIT® MDS TP 220

Lewatit® MDS TP 220 is a macroporous weakly basic resin with chelating bis-picolylamine groups attached to a styrene/divinylbenzene co-polymer. Its monodisperse bead size distribution combined with a small mean bead size results in improved adsorption kinetics and an approx. 25% higher copper binding capacity relative to Lewatit® MonoPlus TP 220.

At a pH of 2, heavy metal cations are removed from aqueous solutions consistent with the following selectivity series:
Cu >> Ni2+ > UO2 2+ > Fe3+ > Zn2+ > Co2+ > Cd2+ > Fe2+.

Lewatit® MDS TP 220 is especially suitable for the use in the following applications:

• Purification of cobalt electrolytes (cobalt/nickel separation)
• Separation of nickel/copper from ferric solutions
• Recovery of copper from strongly acidic solutions (pH < 2)
• Purification of chromium(III) baths (removal of heavy metals such as copper and nickel)
• Adsorption of heavy metals (e.g. copper) from solutions containing strong chelating agents like EDTA

Whilst most metals are removed from the loaded resin with a conventional acid strip, copper can only efficiently be desorbed with ammonia solution.