title: Preparation and characterization of γ-AlOOH @CS magnetic nanoparticle as a novel adsorbent for removing fluoride from drinking water.
abstract: For this study, a novel adsorbent of γ-AlOOH @CS (pseudoboehmite and chitosan shell) magnetic nanoparticles (ACMN) with magnetic separation capabilities was developed to remove fluoride from drinking water. The adsorbent was first characterized, and then its performance in removing fluoride was evaluated. Kinetic data demonstrated rapid fluoride adsorption with more than 80% fluoride adsorption within the initial 20 min and equilibrium reached in 60 min. Based on the results of kinetic and isotherm models, the fluoride adsorption process on the ACMN's surface was a monolayer adsorption on a homogeneous surface. Thermodynamic parameters presented that the adsorption process is spontaneous and endothermic in nature. The mechanism for the adsorption involved electrostatic interaction and hydrogen bonding. Moreover, the calculated adsorption capacity of the ACMN for fluoride using the Langmuir model was 67.5 mg/g (20°C, pH=7.0±0.1), higher than other fluoride removal adsorbents. This nanoadsorbent performed well over a pH range of 4-10. The study found that PO4(3-) was the co-existing anion most able to hinder the nanoparticle's fluoride adsorption, followed by NO3(-) then Cl(-). Experimental results suggest that ACMN is a promising adsorbent for treating fluoride-contaminated water.
authors.affiliation: College of Environment, Hohai University, Nanjing 210098, PR China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Wan
authors.affiliation: Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, PR China; College of Environment, Hohai University, Nanjing 210098, PR China. Electronic address: cwhhu5826@163.com.
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.affiliation: College of Environment, Hohai University, Nanjing 210098, PR China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Liu
authors.affiliation: College of Environment, Hohai University, Nanjing 210098, PR China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Liu
authors.affiliation: College of Environment, Hohai University, Nanjing 210098, PR China.
authors.forename: Changlong
authors.initials: C
authors.lastname: Dong
mesh_terms: D000536:Aluminum Hydroxide / Q000737:chemistry*; D000537:Aluminum Oxide / Q000737:chemistry*; D048271:Chitosan / Q000737:chemistry*; D060766:Drinking Water / Q000737:chemistry*; D005459:Fluorides / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D015233:Models, Statistical; D010710:Phosphates / Q000302:isolation & purification*; D056951:Photoelectron Spectroscopy; D013816:Thermodynamics
chemical_list: D060766:Drinking Water; D058185:Magnetite Nanoparticles; D010710:Phosphates; C012980:fluorophosphate; D000536:Aluminum Hydroxide; C069471:aluminum oxide hydroxide; D048271:Chitosan; D000537:Aluminum Oxide; D005459:Fluorides
keywords: Adsorption; Chitosan; Fluoride; Magnetic nanoparticle; Pseudoboehmite