title: Adsorption of aluminum and lead from wastewater by chitosan-tannic acid modified biopolymers: Isotherms, kinetics, thermodynamics and process mechanism.
abstract: Chitosan was reacted by tannic acid to obtain three modified chitosan biopolymer. Their chemical structures were characterized by FTIR and elemental analysis. The prepared biopolymers were used to adsorb Al(III) and Pb(II) metal ions from industrial wastewater. The factors affecting the adsorption process were biosorbent amount, initial concentration of metal ion and pH of the medium. The adsorption efficiency increased considerably with the increase of the biosorbent amount and pH of the medium. The adsorption process of biosorbent on different metal ions was fitted by Freundlich adsorption model. The adsorption kinetics was followed Pseudo-second-order kinetic model. The adsorption process occurred according to diffusion mechanism which was confirmed by the interparticle diffusion model. The modified biopolymers were efficient biosorbents for removal of Pb(II) and Al(III) metal ions from the medium.
authors.affiliation: Chemistry Department, Faculty of Science, Cairo University, Giza, Egypt.
authors.forename: M A
authors.initials: MA
authors.lastname: Badawi
authors.affiliation: Petrochemicals Department, Egyptian Petroleum Research Institute, Nasr City, Cairo, Egypt. Electronic address: nabelnegm@hotmail.com.
authors.forename: N A
authors.initials: NA
authors.lastname: Negm
authors.affiliation: National Institute of Laser Enhanced Sciences, Cairo University, Giza, Egypt.
authors.forename: M T H
authors.initials: MTH
authors.lastname: Abou Kana
authors.affiliation: Petrochemicals Department, Egyptian Petroleum Research Institute, Nasr City, Cairo, Egypt.
authors.forename: H H
authors.initials: HH
authors.lastname: Hefni
authors.affiliation: Chemistry Department, Faculty of Science, Cairo University, Giza, Egypt.
authors.forename: M M
authors.initials: MM
authors.lastname: Abdel Moneem
mesh_terms: D000327:Adsorption; D000535:Aluminum / Q000737:chemistry* / Q000302:isolation & purification*; D048271:Chitosan / Q000737:chemistry*; D004058:Diffusion; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D007854:Lead / Q000737:chemistry* / Q000302:isolation & purification*; D013634:Tannins / Q000737:chemistry*; D013816:Thermodynamics; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D000535:Aluminum; D048271:Chitosan; D007854:Lead; D013634:Tannins; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Adsorption isotherm; Chitosan; Kinetic models; Metal removal; Tannic acid; pH