ADSORPTION STUDY OF LEAD BY ASCOPHYLLUM NODOSUM USING A FACTORIAL EXPERIMENTAL DESIGN

A factorial design methodology was used to evaluate the effects of temperature, pH and initial concentration of Pb(II) in sorption process onto the marine macro-algae

Ascophyllum nodosum

. The Box-Behnken factorial design method gives a mathematical model that shows the influence of each variable and their interactions on the process efficiency. Study ranges were 10-40 °C for temperature, 3.00-5.00 for pH and 50-200 mg/L for initial Pb(II) concentration. Within these ranges, the adsorption capacity is slightly dependent on temperature and pH but markedly increases with initial concentration. Maximum adsorption capacity of Pb(II) by

Ascophyllum nodosum

was 180 mg/g, which corresponds to the following values of those variables: temperature = 40 °C, pH = 5.00 and initial concentration = 200 mg/L.