title: Removal of fluoride from aqueous solution using Zr(IV) immobilized cross-linked chitosan.
abstract: In the present paper, zirconium immobilized cross-linked chitosan (Zr-CCS) was reported for the adsorption of fluoride. Zr-CCS was synthesized by methods of membrane-forming and subsequent cross-linking reaction. Zr-CCS was characterized by FTIR, XRD, and SEM technologies. Batch adsorption experiments were performed to evaluate the adsorption capacity of Zr-CCS toward fluoride. The adsorption of fluoride onto the Zr-CCS favored at low pH values, and reduced in the presence of other co-anions. The adsorption equilibrium data had a good agreement with the Langmuir isotherm model, and the maximum adsorption capacity was calculated as 48.26mg/g for fluoride at 303K and natural pH (6.0). Thermodynamic parameters indicate that the nature of fluoride adsorption was spontaneous and endothermic. The adsorption mechanism of fluoride onto the Zr-CCS was controlled by chemical ion-exchange and electrostatic attraction between Zr-CCS and fluoride.
authors: College of Science, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors: Qian
authors: Q
authors: Liu
authors: College of Science, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors: Lujie
authors: L
authors: Zhang
authors: Xi'an Institute of Geology and Mineral Resource, Xi'an, Shaanxi 710054, China.
authors: Bingchao
authors: B
authors: Yang
authors: College of Science, Northwest A&F University, Yangling, Shaanxi 712100, China. Electronic address: hrh20022002@163.com.
authors: Ruihua
authors: R
authors: Huang
mesh_terms: D000327:Adsorption; D048271:Chitosan / Q000737:chemistry*; D005459:Fluorides / Q000737:chemistry* / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D012996:Solutions; D013816:Thermodynamics; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000302:isolation & purification*; D015040:Zirconium / Q000737:chemistry*
chemical_list: D012996:Solutions; D014874:Water Pollutants, Chemical; D048271:Chitosan; D015040:Zirconium; D005459:Fluorides
keywords: Adsorption; Kinetics; Zr-CCS