title: Biosorption and retention of orthophosphate onto Ca(OH)2-pretreated biomass of Phragmites sp.
abstract: The biosorption of phosphorus in the form of orthophosphate (Po) from wastewater using biomass as the sorbent is of potential importance because the Po-loaded biomass could be applied in the agricultural sector as fertilizer and soil conditioner. However, biomass generally displays a very low affinity for Po sorption and therefore biomass surface modification is required. In the present study, the biomass (as model grinded leaves of Phragmites sp. were used) was pretreated with Ca(OH)2 to enhance Po biosorption capacity (qe). The results indicate that the alkaline pretreatment resulted in a modification of surface functional groups. It was concluded that the main sorption mechanisms were ligand exchange and electrostatic attraction. A series of experiments were conducted to investigate the performance of the pretreated biomass for Po uptake under various conditions. Isotherm and thermodynamic studies were also applied and analyzed. The biosorption process was best described by the pseudo-second order kinetic model and Langmuir isotherm, which gave a qmax of 12.27mgP/g at 25°C and pH7. The Ca(OH)2 treated Phragmites biomass applied in this study for Po recovery may present some potential advantages in terms of costs and environmental impact.
authors.affiliation: Department of Natural Resources Management and Agricultural Engineering, Agricultural University of Athens, Iera Odos 75, Athens 11855, Greece. Electronic address: markougior@gmail.com.
authors.forename: Giorgos
authors.initials: G
authors.lastname: Markou
authors.affiliation: Department of Natural Resources Management and Agricultural Engineering, Agricultural University of Athens, Iera Odos 75, Athens 11855, Greece.
authors.forename: Dimitris
authors.initials: D
authors.lastname: Mitrogiannis
authors.affiliation: Laboratory Aquatic Biology, KU Leuven Kulak, E. Sabbelaan 53, Kortrijk 8500, Belgium.
authors.forename: Koenraad
authors.initials: K
authors.lastname: Muylaert
authors.affiliation: Department of Biology, Faculty of Art and Science, Gaziantep University, Gaziantep 27310, Turkey.
authors.forename: Abuzer
authors.initials: A
authors.lastname: Çelekli
authors.affiliation: Department of Food Engineering, Faculty of Engineering, Gaziantep University, Gaziantep 27310, Turkey.
authors.forename: Hüseyin
authors.initials: H
authors.lastname: Bozkurt
mesh_terms: D000327:Adsorption; D001673:Biodegradation, Environmental; D018533:Biomass; D002126:Calcium Hydroxide / Q000737:chemistry*; D010710:Phosphates / Q000378:metabolism*; D006109:Poaceae / Q000378:metabolism*; D013816:Thermodynamics; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D010710:Phosphates; D014874:Water Pollutants, Chemical; D002126:Calcium Hydroxide
keywords: Biosorption; Ligand exchange; Nutrient recovery; Phosphorus removal; Pretreatment