| Abstract |
| Mercapto-impregnated mesoporous silica has been developed for the removal of Hg(Ⅱ), Cd(Ⅱ) and Pb(Ⅱ) ions by adsorption. Mesoporous silica used for heavy metals adsorbents were prepared by co-condensation of surfactant as a template and Ludox HS-40 as a silica precursor. These materials have been characterized by elemental analysis, XRD, SEM and TEM analysis. To elucidate the surface characteristic of adsorbents, the zeta potentials were measured. As a result of zeta potential data, mesoporous silica indicated that the surface potentials seem to be dependent on the pH and the low negative charge showed in the range of all pH. Otherwise, the surface potentials of mercapto-impregnated mesoporous silica indicated that positive charge at the pH 3～8. Mercapto-impregnated mesoporous silica effectively removed Hg(Ⅱ) over 87 % from 40 ppm Hg aqueous solution at pH 6.2～6.5 and removed Cd(Ⅱ) over 81 % from 40 ppm Pb aqueous solution and removed Pb(Ⅱ) over 78%, respectively. The removal selectivity by the mercapto- impregnated mesoporous silica was in the order of Hg > Cd > Pb. |
|
|
| Key Words |
| Mesoporous silica, Mercapto-impregnated mesoporous silica, Hazardous heavy metal, zeta potential |
|
|
|
|
|
PDF