Biomass sorbents for metalloid removal

The present work investigates the sorption of metalloids - As(V), Sb(V), and Te(VI) - on Fe-modified biomaterials (Fe-modified peat, shingles, moss, straw, canes, and sand) using batch tests. The said sorption was studied as a function of initial metalloid concentration, pH, and temperature. The highest sorption capacity was observed for Fe-modified peat. Fe-modified moss and Fe-modified shingles can also be used in severely polluted waters. The best sorption conditions are in the pH interval 3-6.5 for As(V) and Sb(V), while pH 3-9 is the most appropriate interval for Te(VI) removal. The impact of temperature on the metalloid sorption capacity of Fe-modified peat was tested at four temperatures: 275, 283, 298, and 313 K, and the sorption capacity increased with increase in temperature for all of the studied metalloids. The calculated thermodynamic parameters suggest that the sorption process is of a spontaneous nature and endothermic.