Study of the equilibrium of uptake and biosorption of cadmium (II) by algae marine ulva lactuca) Etude des équilibres d'absorption et biosorption du cadmium (II) par des algues marines ulva-lactuca

Wastewater contaminated by heavy metals remains today one of the major problems to solve in industrialized countries. various conventional methods are used to remove heavy metals from the existent wastewater. they are based on chemical precipitation phenomena,ion exchanges,and adsorption or bio-sorption. the treatment by plants (phytopurification) is a natural treatment for a variety of aquatic or semi aquatic artificially organized and structured to maximize their holding capacity for various pollution parameters. many studies aim to increase the removal of heavy metals by plants to clean up wastewater. in this study we are interested in the ability of the algae ulva.lactuca to eliminate the cadmium (cd) from a previously prepared solution and the factors that may influence the absorption. the parameters studied were ph,mass,contact time between polluted water and algae (biomass and its impact on the bio-sorption also other physico-chemical parameters).the results show the bio-sorption percentage r% = 93% is observed at ph = 5 and m = 5g amount of living biomass,and the elimination percentage of cd is equal to 98% at ph = 5,m = 1g and c0 = 38.17 mg.l-1 and the amount adsorbed can reach 1.88 mg.g-1 for crushed algae. these results are consistent with those obtained with the langmuir model.