The adsorption of metal ions by Rice Husk Ash

摘要

The adsorption of some metal ions such as Fe3+, Pb2+, Cu2+, Cd2+, Zn2+ adsorbed by rice husk ash(RHA) are studied. The results show that the isotherm adsorption curves for these metal ions are in agree with Langmuir equation, and the adsorption amounts are in the order of following: Fe3+> Pb2+>Cu2+>Cd2+??Zn2+. All these metal ions can reverse the sign of the zeta potential from negative to positive, and the concentrations of zero charge point for Fe3+, Pb2+, Cu2+, Cd2+, Zn2+ are 8.5×10-5, 8×10-3, 0.12, 0.16, 0.18 (mol·L-1 )respectively. Using the electronic double layer model, the adsorption energy is calculated.