The sorption of mercury(II) from aqueous medium on a chelating resin Chelex 100 has been studied in batch mode. Since the extraction
kinetic was obtained, with a mixture of 0.1 g of resin and 5 mL of mercury(II) at 200.59 mg L-1 of initial concentration, extraction
equilibrium was reached within 180 min of mixing. The influence of some parameters such as initial mercury(II) ion concentration, initial
pH of aqueous solution, ion strength and the amounts of resin have been studied at fixed temperature (20±1 °C). The optimum pH value
level for quantitative sorption was 5.7. The best performance obtained was 98.0 % of extraction yield equivalent to 14.19 mg g-1 of resin.
The pseudo-first- order equation, pseudo-second-order equation, the intra-particle diffusion model and Boyd’s diffusivity model were used
to describe the kinetics data and rate constants were evaluated. The Freundlich and Langmuir adsorption models were applied to describe
the equilibrium isotherms.
Key words: mercury(II); Chelex 100; adsorption; ion exchange; optimization.
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