Lewatit® MonoPlus TP 260 is a weakly acidic, macroporous cation exchange resin with chelating amino methyl phosphonic acid groups for the selective removal of transition heavy metals and alkaline earth cations. The monodisperse beads are mechanically and osmotically superior stable. The optimized kinetics lead to an increased operating capacity compared to ion exchange resins with heterodisperse bead size distribution. Divalent cations are removed from neutralized waters int eh following order: Uranium (UO2>Lead>Copper>Zin>Nickel>Cadmium>cobalt>Magnesium>Strontium>Barium>>>Sodium. An adsorption of trivalent cations takes place, but desorption may be difficult. For instance iron (III) can only be desorbed by uneconomically high amounts of specific acid dosage. It is e.g. suitable for a use in:- the secondary purification of brine feed to chloralkali membrane cells (traces of alkaline earth ions are removed after their normal precipitation by carbonates in the pH-range 8-11) at absence of iron (III) ions and in case of low demand on Sr and Ba removal
- the removal of uranium from crude phosphoric acid
- the removal of titanium from recycled battery acid
- the removal of antimony (Sb) and bismuth (Bi) from copper containing electrolytes
- the removal of aluminum from urea solutions
- the removal of fluoride with aluminum doped Lewatit MonoPlus TP 260
- the removal of lead and strontium from BF4 containing waste water out of PCB production
- the removal or iron (II), nickel and zinc from 5% gluconate containing metal working liquid
In brine purification the operating capacity of Lewatit MonoPlus TP 260 depends on the pH-value of the brine. At pH 10 it is approx. threefold of that achieved at pH7. At pH 10 and calcium content of 5 ppm, a capacity up to 15 g Ca/l Lewatit MonoPlus TP 260 (volume of resin in di-sodium-form) is obtained. At a service flow rate of 20-30 BV/h, the residual calcium concentration is well below 20 ppb. Greater security can be achieved by operating two units of equal size in series. Lewatit MonoPlus TP 260 has to be conditioned with caustic soda solution after every regeneration cycle/before every exhaustion cycle. After the conditioning it is in the di-sodium-form and ready to use for the final polishing of chlorakali brine feed.Information provided by Lanxess. |