title: Removal of an anionic dye (Acid Blue 92) by coagulation-flocculation using chitosan.
abstract: Chitosan (a biopolymer) is an aminopolysaccharide that can be used for the treatment of colored solutions by coagulation-flocculation (as an alternative to more conventional processes such as sorption). Acid Blue 92 (a sulfonic dye) was selected as a model dye for verifying chitosan's ability to treat textile wastewater. A preliminary experiment demonstrated that chitosan was more efficient at color removal in tap water than in demineralized water, and that a substantially lower concentration of chitosan could be used with tap water. Dye removal reached up to 99% under optimum concentration; i.e., in terms of the acidic solutions and the stoichiometric ratio between the amine groups of the biopolymer and the sulfonic groups in the dye. The flocs were recovered and the dye was efficiently removed using alkaline solutions (0.001-1 M NaOH solutions) and the biopolymer, re-dissolved in acetic acid solution, was reused in a further treatment cycle.
authors.affiliation: Universitat Politècnica de Catalunya, Departament d'Enginyeria Química, EPSEVG, Av. Victor Balaguer, s/n, E-08800 Vilanova i la Geltrú, Spain.
authors.forename: Agata
authors.initials: A
authors.lastname: Szyguła
authors.forename: Eric
authors.initials: E
authors.lastname: Guibal
authors.forename: María
authors.initials: M
authors.lastname: Ariño Palacín
authors.forename: Montserrat
authors.initials: M
authors.lastname: Ruiz
authors.forename: Ana Maria
authors.initials: AM
authors.lastname: Sastre
mesh_terms: D000838:Anions / Q000737:chemistry*; D048271:Chitosan / Q000737:chemistry*; D004396:Coloring Agents / Q000737:chemistry*; D005427:Flocculation; D014874:Water Pollutants, Chemical / Q000737:chemistry; D018508:Water Purification / Q000379:methods*; D014881:Water Supply
chemical_list: D000838:Anions; D004396:Coloring Agents; D014874:Water Pollutants, Chemical; D048271:Chitosan