The adsorption behaviors of Fe-Mn binary oxide towards Sb(V)
铁锰复合氧化物吸附去除五价锑性能研究

The adsorption characteristics of antimonate (Sb(V)) polluted water by Fe-Mn binary oxide (FMBO) was studied and compared with FeOOH and MnO2. The results indicated FMBO had strong adsorption ability to Sb(V) and the maximum adsorption capacity at pH 5.0 was 1.05 mmol·g-1, which was higher than FeOOH (0.82 mmol·g-1) and MnO2 (0.43 mmol·g-1). The Freundlich model best described the adsorption behavior of Sb(V) by FMBO (R2 = 0.98). The Pseudo-second-order model was able to describe the adsorption kinetics of Sb(V) onto FMBO (R2 = 0.93) and MnO2 (R2 = 0.96), while the Elovich model fitted best for the adsorption process of Sb(V) onto FeOOH (R2 = 0.94). Sb(V) removal by FMBO was evidently dependent on pH with the greatest adsorption occurring under acidic conditions and decreased with increase in solution pH. With the exception of phosphate, normally present ions such as carbonate and sulfate had no obvious side effect on antimonate adsorption by FMBO. Sb(V) removal was promoted under higher ion strength conditions indicating that the Sb(V) removal was achieved by the formation of inner-sphere surface complexes at the water/oxide interface on FMBO.