title: Fluoride adsorption on carboxylated aerobic granules containing Ce(III).
abstract: Aerobic granules (AG) were carboxylated and Ce(III) was incorporated to obtain modified granuels (Ce(III)-MAG) for removal of fluoride from aqueous solutions. The Ce(III)-MAG was characterized by SEM, FTIR, XRD and pH(pzc), and the introduction of carboxyl groups and Ce(III) was confirmed. The adsorption capacity of Ce(III)-MAG for fluoride was 45.80 mg/g at neutral pH, an increase of 359% compared to the capacity of pristine AG. Adsorption was highest at pH range of 3.0-5.0. A positive effect on fluoride removal in the order of K(+) ≈ Mg(2+) > Ca(2+) > Na(+) and a negative effect in the order of NO(3)(-) > Cl(-) > SO(4)(2-) > HCO(3)(-) > PO(4)(3-) was observed. Fluoride adsorption followed the Redlich-Peterson model and the pseudo-first order model with correlation factors of 0.999 and 0.950, respectively. Ce(III)-MAG held up to 790 bed volumes and the effluent fluoride concentration remained below 1.0mg/L (influent fluoride 10mg/L).
authors.affiliation: Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100, China. xinhuawang@sdu.edu.cn
authors.forename: Xin-Hua
authors.initials: XH
authors.lastname: Wang
authors.forename: Rui-Hong
authors.initials: RH
authors.lastname: Song
authors.forename: Hui-Chun
authors.initials: HC
authors.lastname: Yang
authors.forename: Yi-Jing
authors.initials: YJ
authors.lastname: Shi
authors.forename: Guang-Bin
authors.initials: GB
authors.lastname: Dang
authors.forename: Sen
authors.initials: S
authors.lastname: Yang
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhao
authors.forename: Xue-Fei
authors.initials: XF
authors.lastname: Sun
authors.forename: Shu-Guang
authors.initials: SG
authors.lastname: Wang
mesh_terms: D000327:Adsorption; D001420:Bacteria, Aerobic / Q000737:chemistry*; D002563:Cerium / Q000032:analysis*; D005459:Fluorides / Q000032:analysis / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008855:Microscopy, Electron, Scanning; D017550:Spectroscopy, Fourier Transform Infrared; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*; D014961:X-Ray Diffraction
chemical_list: D014874:Water Pollutants, Chemical; D002563:Cerium; D005459:Fluorides