title: Pre-treatment of industrial wastewater polluted with lead using adsorbents and ultrafiltration or microfiltration membranes.
abstract: This work investigated the use of ultrafiltration (UF) or microfiltration (MF) membranes combined with natural minerals for the pre-treatment of wastewater containing high amounts of lead. The effects of initial lead concentration, solution pH, membrane pore size, mineral type and concentration and mineral - metal contact time were investigated. Lead removal accomplished by the UF system was higher in wastewater compared to that obtained in aqueous solutions and this was attributed to the formation of insoluble metal precipitates/complexes, which were effectively retained by the membranes. At pH = 6 the dominant removal mechanism was precipitation/complexation, while mineral adsorption enhanced lead removal. The combined use of minerals and UF/MF membranes can effectively remove lead from wastewater resulting in a final effluent that can be further treated biologically with no biomass inhibition problems or can be safely discharged into municipal sewers. Kinetics investigation revealed a two-stage diffusion process for all minerals employed. The Langmuir isotherm exhibited the best fit to the experimental data.
authors.affiliation: National Technical University of Athens, Department of Chemical Engineering, 9 Iroon Polytechniou St., Zographou Campus; PC 157 73 Athens, Greece. ekatsou@yahoo.gr
authors.forename: Evina
authors.initials: E
authors.lastname: Katsou
authors.forename: Simos
authors.initials: S
authors.lastname: Malamis
authors.forename: Katherine
authors.initials: K
authors.lastname: Haralambous
mesh_terms: D000327:Adsorption; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste; D007700:Kinetics; D007854:Lead / Q000737:chemistry*; D008567:Membranes, Artificial; D008962:Models, Theoretical; D014462:Ultrafiltration / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D007220:Industrial Waste; D008567:Membranes, Artificial; D014874:Water Pollutants, Chemical; D007854:Lead