title: Preparation, characterization of electrospun meso-hydroxylapatite nanofibers and their sorptions on Co(II).
abstract: In this work, mesoporous hydroxylapatite (meso-HA) nanofibers were prepared via calcination process with polyvinyl alcohol/HA (PVA/HA) hybrid nanofibers fabricated by electrospinning technique as precursors, and the removal efficiency of meso-HA nanofibers toward Co(II) was evaluated via sorption kinetics and sorption isotherms. Furthermore, the sorption behaviors of Co(II) on meso-HA nanofibers were explored as a function of pH, ionic strength, and thermodynamic parameters. There existed hydrogen bonds between HA and PVA matrix in precursor nanofibers which could change into meso-HA nanofibers with main pore diameter at 27nm and specific surface area at 114.26m(2)/g by calcination process. The sorption of Co(II) on meso-HA was strongly dependent on pH and ionic strength. Outer-sphere surface complexation or ion exchange was the main mechanisms of Co(II) adsorption on meso-HA at low pH, whereas inner-sphere surface complexation was the main adsorption mechanism at high pH. The sorption kinetic data were well fitted by the pseudo-second-order rate equation. The sorption isotherms could be well described by the Langmuir model. The thermodynamic parameters (ΔH°, ΔS° and ΔG°) calculated from the temperature-dependent sorption isotherms suggested that the sorption process of Co(II) on meso-HA nanofibers was spontaneous and endothermic.
authors.affiliation: School of Chemical Technology, Hefei University of Technology, Hefei, Anhui 230009, PR China. Electronic address: hlwang@hfut.edu.cn.
authors.forename: Hualin
authors.initials: H
authors.lastname: Wang
authors.affiliation: School of Chemical Technology, Hefei University of Technology, Hefei, Anhui 230009, PR China.
authors.forename: Peng
authors.initials: P
authors.lastname: Zhang
authors.affiliation: School of Chemical Technology, Hefei University of Technology, Hefei, Anhui 230009, PR China.
authors.forename: Xingkong
authors.initials: X
authors.lastname: Ma
authors.affiliation: School of Chemical Technology, Hefei University of Technology, Hefei, Anhui 230009, PR China.
authors.forename: Suwei
authors.initials: S
authors.lastname: Jiang
authors.affiliation: School of Chemical Technology, Hefei University of Technology, Hefei, Anhui 230009, PR China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Huang
authors.affiliation: School of Chemical Technology, Hefei University of Technology, Hefei, Anhui 230009, PR China.
authors.forename: Linfeng
authors.initials: L
authors.lastname: Zhai
authors.affiliation: School of Biotechnology and Food Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China.
authors.forename: Shaotong
authors.initials: S
authors.lastname: Jiang
mesh_terms: D000327:Adsorption; D003035:Cobalt / Q000737:chemistry*; D017886:Durapatite / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D057139:Nanofibers / Q000737:chemistry* / Q000648:ultrastructure; D009994:Osmolar Concentration; D056951:Photoelectron Spectroscopy; D011142:Polyvinyl Alcohol / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D014865:Waste Disposal, Fluid / Q000379:methods; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D014874:Water Pollutants, Chemical; D003035:Cobalt; D011142:Polyvinyl Alcohol; D017886:Durapatite
keywords: Electrospinning technique; Meso-HA nanofiber; PVA/HA hybrid nanofiber; Removal cobalt(II)