Pretreated biomass of marine macroalgae as low cost high efficiency adsorbent for heavy metal ions

Environmental pollution from industrial wastewater that contains heavy meta ls is an important issue in many countries. Cost effective technologies for the removal and recovery of the heavy metals are needed. Recently, much in terest has been devoted to the processes of biosorption of heavy metals, in which various types of biomass, such as bacteria, fungi, and algae, are us ed as adsorbents for heavy metal ions. In this paper, the pretreated biomas s (biosorbent) of a group of marine macroalgae was evaluated for its biosor ption properties. The chemical and mechanical stabilities of the biomass we re much improved by using pretreatment methods. The microstructures of the biomass were obtained by using electron microscopy. The heavy metal uptake capacities of the biosorbents ranged from 0.8-1.5 mmol/g (dry wt) for a num ber of divalent heavy metal ions. The capacities were higher than most othe r types of biomass and were comparable to commercial ion exchange resins. T he kinetics of the biosorption process and the fixed-bed breakthrough curve s were also studied. This study indicated that the biosorbents derived from the biomass of marine macroalgae could be used as highly effective adsorbe nt for the removal and recovery of heavy metal ions from industrial wastewa ter.