title: Removal of copper(II) ions by a biosorbent--Cinnamomum camphora leaves powder.
abstract: In the present study, Cinnamomum camphora leaves powder (CLP) was investigated as a biosorbent for the removal of copper ions from aqueous solutions. The biosorbents before and after adsorption were measured by EDS and FT-IR. Kinetic data and sorption equilibrium isotherms were carried out in batch process. The adsorption kinetic experiments revealed that there are three stages in the whole adsorption process. It was found that Cu(II) adsorption onto CLP for different initial Cu(II) concentrations all followed pseudo-second order kinetics and were mainly controlled by the film diffusion mechanism. Batch equilibrium results at different temperatures suggest that Cu(II) adsorption onto CLP can be described perfectly with Langmuir isotherm model compared to Freundlich and D-R isotherm models, and the characteristic parameters for each adsorption isotherm were also determined. Thermodynamic parameters calculated show that the adsorption process has been found to be endothermic in nature. The analysis for the values of the mean free energies of adsorption (E(a)), the Gibbs free energy (DeltaG(0)) and the effect of ionic strength all demonstrate that the whole adsorption process is mainly dominated by ion-exchange mechanism, accompanied by a certain amount of surface complexation which has been verified by variations in EDS and FT-IR spectra and pH value before and after adsorption. Regeneration studies show CLP possesses an excellent reusability.
authors.affiliation: School of Pharmaceutical and Chemical Engineering, Taizhou University, Dongfang Road No 605, Linhai 317000, Zhejiang, PR China. chenhao2212@sohu.com
authors.forename: Hao
authors.initials: H
authors.lastname: Chen
authors.forename: Guoliang
authors.initials: G
authors.lastname: Dai
authors.forename: Jie
authors.initials: J
authors.lastname: Zhao
authors.forename: Aiguo
authors.initials: A
authors.lastname: Zhong
authors.forename: Junyong
authors.initials: J
authors.lastname: Wu
authors.forename: Hua
authors.initials: H
authors.lastname: Yan
mesh_terms: D000327:Adsorption; D027423:Cinnamomum camphora; D003300:Copper / Q000302:isolation & purification*; D018515:Plant Leaves / Q000737:chemistry*; D013816:Thermodynamics; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods
chemical_list: D014874:Water Pollutants, Chemical; D003300:Copper