title: Response surface methodology for cadmium biosorption on Pseudomonas aeruginosa.
abstract: In this research the effects of various physicochemical factors on Cd(2+) biosorption such as initial metal concentration, pH and contact exposure time were studied. This study has shown a Cd(2+) biosorption, equilibrium time of about 5 min for Pseudomonas aeruginosa and the adsorption equilibrium data were well described by Langmuir equation. The maximum capacity for biosorption has been extrapolated to 0.56 mmol.g(-1) for P. aeruginosa. The thermodynamic properties ΔG(0), ΔH(0), and ΔS(0) of Cd(2+) for biosorption were analyzed by the equilibrium constant value obtained from experimented data at different temperatures. The results show that biosorption of Cd(2+) by P. aeruginosa are endothermic and spontaneous with ΔH value of 36.35 J.mol(-1). By response surface methodology, the quadratic model has adequately described the experimental data based on the adjusted determination coefficient (R(2) = 0.98). The optimum conditions for maximum uptake onto the biosorbent were established at 0.5 g.l(-1) biosorbent concentration, pH 6 for the aqueous solution, and a temperature of 30 °C.
authors.affiliation: Department of Molecular and Cell Biology, Faculty of Basic Science, University of Mazandaran, P.O. Box 47416-95447, Babolsar, Iran E-mail: sahmadyas@yahoo.fr; sa.ahmadi@umz.ac.ir.
authors.forename: Salman
authors.initials: S
authors.lastname: Ahmady-Asbchin
mesh_terms: D000327:Adsorption; D002104:Cadmium / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008962:Models, Theoretical; D011550:Pseudomonas aeruginosa / Q000737:chemistry*; D013696:Temperature; D013816:Thermodynamics
chemical_list: D002104:Cadmium