Biosorption of Cadmium and Lead from Aqueous Solutions by Chlorella vulgaris Biomass: Equilibrium and Kinetic Study

Biosorption of cadmium and lead from aqueous solution was investigated using green algae Chlorella vulgaris at room temperature and at pH adjusted to 7.0. Various sorption parameters such as contact time, initial metal ion concentration and biomass quantity were studied. The equilibrium experimental data are well represented by Langmuir model among two-parameter models. It was noted that the maximum adsorption capacity for cadmium and lead was 149.9 and 178.5 mg (metal) g(-1) biomass, respectively. The kinetic data were fitted by models including pseudo-first order and pseudo-second order. It was observed that, the pseudo-first-order kinetic model describes the biosorption of cadmium and lead ions onto C. vulgaris biomass.