title: Cu(II) adsorption from copper mine water by chitosan films and the matrix effects.
abstract: Adsorption of copper ions onto chitosan films was studied, and the matrix effect was evaluated using a synthetic solution and a real effluent from closed copper mine. Chitosan films were prepared by casting technique and characterized. The adsorption study was carried out by equilibrium isotherms, thermodynamics, and kinetics. The thermodynamic parameters indicated that the copper adsorption onto chitosan film was favorable, spontaneous, and exothermic, suggesting an increased randomness at the solid/solution interface. The matrix effect was evaluated in kinetic assays, where a synthetic solution and a real system were carried out at different stirring rates. The highest values of adsorption capacity reached in all stirring rates were about 20% lower in the real effluent, and this reduction in the competitiveness was due to the presence of other ions in the matrix of the real effluent. The maximum adsorption capacity of copper ions onto chitosan films for the synthetic solution was of 450 mg g-1, and the removal percentage was in the range from 78 to 96%, and these values for the real effluent were of 360 mg g-1and removal ranging from 62 to 76%. The mapping done of ions present in the water adsorbed of the mine in the films showed that the same was homogeneously distributed in the films' surfaces.
authors.affiliation: School of Chemistry and Food, Federal University of Rio Grande (FURG), FURG, km 8 Itália Avenue, Carreiros District, Rio Grande, RS, Brazil.
authors.forename: Tuanny S
authors.initials: TS
authors.lastname: Frantz
authors.affiliation: School of Chemistry and Food, Federal University of Rio Grande (FURG), FURG, km 8 Itália Avenue, Carreiros District, Rio Grande, RS, Brazil.
authors.forename: Nauro
authors.initials: N
authors.lastname: Silveira
authors.affiliation: Engineering Department, Federal University of Pelotas (UFPel), Pelotas, RS, Brazil.
authors.forename: Maurízio S
authors.initials: MS
authors.lastname: Quadro
authors.affiliation: Engineering Department, Federal University of Pelotas (UFPel), Pelotas, RS, Brazil.
authors.forename: Robson
authors.initials: R
authors.lastname: Andreazza
authors.affiliation: Engineering Department, Federal University of Pelotas (UFPel), Pelotas, RS, Brazil.
authors.forename: Amauri A
authors.initials: AA
authors.lastname: Barcelos
authors.affiliation: School of Chemistry and Food, Federal University of Rio Grande (FURG), FURG, km 8 Itália Avenue, Carreiros District, Rio Grande, RS, Brazil.
authors.forename: Tito R S
authors.initials: TRS
authors.lastname: Cadaval
authors.affiliation: School of Chemistry and Food, Federal University of Rio Grande (FURG), FURG, km 8 Itália Avenue, Carreiros District, Rio Grande, RS, Brazil. dqmpinto@furg.br.
authors.forename: Luiz A A
authors.initials: LAA
authors.lastname: Pinto
mesh_terms: D000327:Adsorption; D048271:Chitosan / Q000737:chemistry*; D003300:Copper / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D012996:Solutions; D013816:Thermodynamics; D062065:Wastewater / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods
chemical_list: D048271:Chitosan; D003300:Copper; D012996:Solutions; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Adsorption; Chitosan film; Copper ions; Matrix effect; Wastewater