Lewatit® TP 207 is a weakly acidic, macroporous cation exchange resin with chelating iminodiacetat groups for the selective extraction of heavy metal cations from weakly acidic to weakly basic solutions. Divalent cations are removed from neutralized waters in the following order: Copper>Vanadium (VO2)>Uranium (UO2)>Lead>Nickel>Zinc>Cadmium>Iron (II)>Beryllium>Manganese> Calcium>Magnesium>Strontium>Barium>>>Sodium. It is especially suitable for use in the following applications:- the selective removal of trace heavy metals from effluents of the metal surface finishing industry, even in the presence of high calcium concentrations
- the recovery of useful metals from electroplating rinse waters
- the removal of metal contaminants from processing baths
- the concentration, extraction and recovery of heavy metals from hydrometallurgical solutions
- the removal of heavy metals from contaminated ground water for the purpose of potable water production or ground water remediation.
The selective extraction is achieved even in the presence of the following complexing agents:- nitrogen compounds, e.g. ammonia, aliphatic and aromatic amines
- multivalent carboxylic acids, e.g. citric acid, gluconic acid, glucuronic acid, oxalic acid, tartaric acid
- phosphates, e.g. tetrasodium diphosphate, sodium polyphosphate
Lewatit TP 207 does not remove heavy metals from solutions containing EDTA or NTA respectively. Only cadmium is removed from solutions containing cyanides. For the extraction of those heavy metals which follow the uranyl oxide ion in the selectivity sequence as shown above. Lewatit TP 207 has to be conditioned with caustic soda solution after every regeneration cycle before every exhaustion cycle. After the conditioning it is partially in a salt-form, e.g. mono-sodium-form.Information provided by Lanxess. |
