Reduction of iron(III) ion by activated carbon fiber

The mechanisms of adsorption of iron(II) ion, iron(III) ion, and reduced ir on(III) ion onto an activated carbon fiber and the ability of carbon fibers to reduce iron(III) ion were investigated on the basis of the amounts of i ron ion adsorbed. The amount of iron(II) ion adsorbed onto the activated ca rbon fiber increased with increasing adsorption temperature. Iron(II) ion w as more easily removed by the activated carbon fiber than iron(III) ion, Ir on(III) ion was adsorbed onto the activated carbon fiber after being reduce d to iron(II) ion. The reduction ability of A-20 was stronger than that of A-10 because the hydrophilic groups of A-20 were larger than those of A-10. It is concluded that the activated carbon fiber has a reduction effect on iron(III) ion and that the reduction effect of the activated carbon fiber d epended on the number of hydrophilic groups on the activated carbon fiber. (C) 2000 Academic Press.