The ceramic-like syntetic composite based on Fe/Mn oxides and MnCO3 as absorbent for the removal of toxic anions, such as arsenite and selenite.

Abstract

This work presents the synthesis and characterization of the ceramic-like inorganic composites based on Fe/Mn oxides and Mn(II) carbonate, and explores their application in adsorptive removal of toxic anions from water. The composites of several Fe-to-Mn ratios were prepared via the urea-supported hydrothermal precipitation approach and further treated at 80 and 300 oC. The obtained materials were tested for their adsorptive removal of the list of target (for water treatment) anions. The sample having the best performance (the greatest affinity for) to arsenite (H3AsO3) and selenite (HSeO3−) was chosen and further investigated as anion exchanger for these anions. The molecular-mechanism of As(III) and Se(IV) adsorption was studied by a number of spectroscopic methods. The possibility of using the best composite sample (based on Fe3+/Mn3+ oxides and MnCO3) under dynamic adsorption conditions (industrial choice of adsorption technology) was confirmed by testing the material performance in adsorption columns.