Ion Exchange Recovery of Palladium(II) from Acidic Solutions Using Monodisperse Lewatit SR-7

This work focuses on the sorption recovery of palladium(II) present in chloride and chloride nitrate(V) solutions on the commercial strongly basic anion exchanger Lewatit Mono Plus SR-7. Sorption, kinetic, and equilibrium studies were carried out using batch and dynamic methods. The basic parameters of sorption capacity, recovery degree, distribution coefficient, process rate, and half-exchange time were calculated. Effects of agitation speed, initial palladium(II) concentration, and total concentration of the chloride anions were tested. Regeneration and reuse of the resin was also investigated. The surface morphology of Lewatit MonoPlus SR-7 before and after the sorption process was described. Lewatit MonoPlus SR-7 is an efficient sorbent for Pd(II) ions (Langmuir capacity 197 mg/g), is characterized by good kinetic properties, and can be regenerated and reused repeatedly without decrease of capacity. Moreover, its capacity is high but decreases in the presence of aluminum ions and slightly increases with the temperature (313 K).