The removal of toxic metals from liquid effluents by ion exchange resins. Part X: Antimony(III) /H+/IONAC SR7

Abstract

The present work investigates the removal of Sb(III) from acidic aqueous solution by the ion exchange resin Ionac SR7. Several experimental parameters were considered in the study: stirring speed of the system (280-1000 min−1), temperature (20-60 °C), aqueous acidity (0.1-2 M HCl), resin dosage (2.5-20 g·L−1) and the source of the aqueous ionic strength. The load of Sb(III) onto the resin is attributable to an anion exchange reaction, being this process exothermic and spontaneous. Based in the experimental data, several modes were tested to explain loading kinetics, loading mechanism and loading isotherm, which respectively are the pseudo-second order kinetic model, the particle-diffusion controlled model and the Freundlich isotherm. The performance of the resin with respect to antimony load was compared against other anion exchanger resins and multiwalled.carbon nanotubes. It was found that water is an effective medium to remove antimony(III) from the metal-loaded resin.