Enhanced iron efficiency of Fe-impregnated granular activated carbon (Fe-GAC) for arsenate removal via Fe(II)-H2O2 method

摘要

In this study, Fe-impregnated granular activated carbon (Fe-GAC) were prepared through the hydrolysis of ferrous sulfate on granular activated carbon (Fe-GAC) by the Fe(II)-H2O2 or Fe(II)-O-2 (air) method at different temperatures. SEM, BET, XRD, XPS and FTIR characterizations revealed that Fe-GAC through Fe(II)-H2O2 method with a reaction time of 24 h resulted in more nanoscale iron hydroxide sulfate hydrate(Fe(2)S(2)O(9)lxH(2)O), whereas Fe-GAC through Fe(II)-O-2 method formed nanoscale iron hydroxide sulfate hydrate with Fe2+. The impregnated iron through the Fe(II)-H2O2 method was more efficiently used for arsenate removal, and the material obtained with a reaction time of 24 h was most effective, indicating Fe2+ in Fe-GAC by Fe(II)-O-2 method and uneven and clustered iron hydroxide sulfate hydrate at 300-500 degrees C resulted in the low iron efficiency. The arsenate adsorption capacity of Fe-GAC increased linearly with the iron. content in the composite material (R-2 > 0.94). The presence of Cl-, SO42-, NO3-, ClO4-, and PO43- displayed various degrees of inhibitive effect on the adsorption of arsenate, but BrO3- promoted the adsorption of arsenate. The new preparation method and the material provide a useful alternative for improved removal of arsenate from contaminated water. (C) 2016 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.