EKOLOJI, vol.19, no.74, pp.77-88, 2010 (SCI-Expanded)
This paper describes a study of the sorptive removal of arsenite (As(III)) from aqueous solutions by synthetically prepared Mg-Fe-based hydrotalcites (FeHT) as layered double hydroxide (LDH) adsorbents. The synthesis of Fe+3-substituted hydrotalcites (FeHT) with the chemical formula [Mg(II)(6)Fe(III)(2)(OH)(16)](+2) [CO3 center dot yH(2)O](-2) was achieved by a co-precipitation method. The reaction product were characterized by powder X-ray diffraction and SEM (Scanning electron microscope) analysis. The influences of solution pH, initial arsenite (As(III)) concentration, and adsorbeut concentration were investigated by the batch experiments to provide an insight into adsorption mechanism of arsenite (As(III)) onto the Mg-Fe-based hydrotalcites (FeHT). The adsorption kinetics indicated that the the adsorption process was best described by the second order kinetic model, The results obtained from the isotherm analysis indicated that the Langmuir isotherm model showed the best fit to the process. According to results of arsenite (As(III)) removal from aqueous solution, FeHT has arsenite removal efficiency; with the ability to reduce the concentration of arsenite in the aqueous solution from an initial value of 300 mu g/Lto <27 mu g/L