A study of the factors controlling the sorption of Cr(VI) on synthetic hydrotalcite
The sorption of chromate ions from aqueous solutions onto a synthetic hydrotalcite and its calcination product was investigated. The interaction of these materials with chromate ions shows that the kinetics of sorption are fast and follow a first-order reversible model. The effects of pH, chromate ion concentration and temperature on the sorption were studied. Solutions containing from 10 to 200 mg L‐1 of Cr(VI) were successfully treated. The sorption capacities of these materials are approximately 1.3 and 2.4 mmol CrO42-, per g, for the hydrotalcite and its calcination product, respectively. The reversibility of the sorption of chromate ions suggests the possible use of the calcined hydrotalcites as recyclable sorbents, which may constitute useful supports for trapping chromate ions.