title: Biosorption of Ni(II) by Fig Male: Optimization and Modeling Using a Full Factorial Design.
abstract: The fig male (FM) is successfully used as biosorbent for Ni(2+) removal. The maximum removal efficiency (96.6%) is obtained at pH ~ 5 for a concentration of 1.70 mmol L(-1) and catalyst dose of 5 g L(-1) in less than 10 minutes. The Ni(2+) uptake follows a pseudo-second-order kinetic, the rate constants increase with increasing temperature, and an activation energy of 55.48 kJ mol(-1) is found. The thermodynamic parameters indicate a spontaneous endothermic bisorption. The isotherm data are fitted by the Langmuir and Dubinin-Radushkevich models. The former indicates a maximum Ni(2+) uptake of 0.459 mmol g(-1), which is higher than that of most biosorbents investigated to date. The FTIR spectra reveal the biosorption mechanism between Ni(2+) and FM functional groups. An empirical modeling is performed by using a 2(3) full factorial design, and a regression equation for Ni(2+) biosorption is determined. The biosorbent mass and pH are the most significant parameters affecting the Ni(2+) biosorption.
authors.affiliation: Laboratory of Engineering Reaction Faculty of Engineering Mechanic and Engineering Processes (USTHB) BP 32, Algiers, Algeria.
authors.forename: F
authors.initials: F
authors.lastname: Madjene
authors.forename: A
authors.initials: A
authors.lastname: Chergui
authors.forename: M
authors.initials: M
authors.lastname: Trari
mesh_terms: D000327:Adsorption; D030681:Ficus / Q000737:chemistry*; D007700:Kinetics; D008962:Models, Theoretical; D009532:Nickel / Q000737:chemistry*; D013816:Thermodynamics; D014865:Waste Disposal, Fluid / Q000379:methods*
chemical_list: D009532:Nickel