Biosorption of lead by Laminaria japonica

Characteristics of biosorption of lead by marine algae, Laminaria japonica, were examined. The biosorption capacity of lead by L. japonica was achieved up to 30％ of its own weight and proportional to the initial lead concentration. However, the opposite result was shown in different initial weight of biomass. Ion exchange reaction between lead ions and calcium ions was observed on lead biosorption with Ca-Ioaded biomass. Stoichiometric coefficient, which can represent the exchange ratio between metal ions and protons during elution process, was determined as 1.39. Therefore, it was concluded that the reaction between lead ions already attached in biomass and protons in bulk solution was not fully stoichiometric ion exchange relation at elution process.