Novel composite sorbents based on carbon fibers decorated with ferric hydroxides-Arsenic removal

Carbon fibers (CF) were prepared by carbonization of cellulose and further deposited with ferric hydroxide (CF-Fe). The synthesized CF and CF-Fe composites were employed to remove arsenate from aqueous solution. CF-Fe samples with different amount of Fe (3, 7, 11, and 20 wt.%) were characterized using SEM-EDX, XPS, FTIR, BET, pH titration, and zeta potential measurements. Batch isotherm studies were performed to determine the As (V) adsorption performance of both raw CF and CF-Fe. CF-Fe composites exhibited significantly higher As (V) adsorption capacity compared with raw CF, namely, 167.95 versus 412.8 mu g/g and for raw CF and CF-Fe (3%), respectively. The presence of Cl- and SO42- only slightly affected the As (V) adsorption, whereas competitive adsorption displayed the highest influence of PO43-, followed by F- and CO32-. The results revealed that both coulombic interactions and surface complexation reactions play important role in the As (V) adsorption process.