Phycoremediation of hexavalent chromium in simulated wastewater by Halopteris scoparia (Linnaeus) Sauvageau (Ochrophyta,Phaeophyceae)

Chromium is one of the problematic heavy metals which is produced by various industries. particularly,hexavalent chromium is an acute carcinogen and more mobile and toxic than trivalent chromium. in this work,the experimental parameters that affect the sorption process of hexavalent chromium by raw biomass of the brown seaweed halopteris scoparia (ochrophyta,phaeophyceae) using batch tests was studied (ph,biomass dosage,contact time,initial metalloid concentration). the elimination of hexavalent chromium was strictly ph dependent,and maximum sorption was obtained at more acidic ph (1-2). the chromium abatement rate exceeds 90% from the first minutes before reaching equilibrium from 15 minutes contact time. the sorption capacity at different initial chromium ion concentrations ranging from 10 to 250 mg/l approximates a total removal (85 - 100%) while the removal efficiency surrounds 40% for concentrations higher than 300 mg/l suggesting the saturation of binding sites of the biomass at higher concentration levels. the isotherm data were found to be well fitted by linear langmuir equation. pseudo-second order model was found appropriate to explain the adsorption kinetics more effectively. this study suggests that the brown seaweed halopteris scoparia could be used as an effective biosorbant for hexavalent chromium removal from aqueous solution.