Effect of Modification of Granular Activated Carbon on Pb(II) Adsorption

The effect of modification of granular activated carbon on Pb(II) adsorption is described. Activated carbons (AC) have been proven to be effective adsorbents for the removal of a wide variety of organic and inorganic pollutants. ACs are widely used to treat waters contaminated with heavy metals because of their well developed porous structures, large surface area and a wide spectrum of surface functional. The surface chemistry of ACs has a major influence on their capacity to adsorb inorganic compounds, especially metallic cations. The decrease of surface area was mainly ascribed to the decrease of the micropore volume. Meanwhile, the specific surface areas or micropore volumes were slightly decreased after the chemical treatment due to the micropore filling or blocking. Nevertheless, the total Pb(II) adsorption of modified GACs was increased with increasing of the NaOH concentration, attributed to the good interaction between Pb(II) ions and polar functional groups on the GACs.