title: Granular ferric hydroxide adsorbent for phosphate removal: demonstration preparation and field study.
abstract: Ferric hydroxide (FHO), which has high phosphate adsorption capacity, was prepared by precipitation at industrial scale and then fabricated via the drum granulation method with cross-linked poly(vinyl alcohol) as the binder. The optimum binder/FHO powder ratio was 0.6 for producing a granular adsorbent with a high phosphate adsorption capacity and stability. The Langmuir maximum adsorption capacities of powder and granular FHOs were 74.07 mg g⁻¹ and 56.18 mg g(-1) at pH 7.0 ± 0.2, respectively, which were higher than those of other reported phosphate adsorbents under neutral or acidic conditions. Phosphate-loaded granular FHO could be regenerated by NaOH solution. Columns containing the granular FHO were used for phosphate removal from ozonated secondary effluents of a municipal wastewater treatment plant at space velocity (SV) of 2 and 5 h⁻¹. During more than 2 months' operation, the average removal percentage of PO(4)(3-) was more than 90% and the turbidity and concentration of CODMn in the effluents were lower than in the influents. In addition, energy dispersive X-ray results suggested that active sites inside the granular FHO were available for phosphate removal. The results demonstrated that granular FHO can be applied as an assist technology for phosphate removal from secondary effluents.
authors.affiliation: Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China E-mail: zhangyu@rcees.ac.cn; Technology Institute of Beijing Waterworks Group Co., Ltd, Beijing 100012, China.
authors.forename: Bei
authors.initials: B
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China E-mail: zhangyu@rcees.ac.cn.
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, China.
authors.forename: Xiaomin
authors.initials: X
authors.lastname: Dou
authors.affiliation: Tianjin Key Laboratory of Aquatic Science and Technology, Tianjin Chengjian University, Tianjin 300384, China.
authors.forename: Hongying
authors.initials: H
authors.lastname: Yuan
authors.affiliation: Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China E-mail: zhangyu@rcees.ac.cn.
authors.forename: Min
authors.initials: M
authors.lastname: Yang
mesh_terms: D000327:Adsorption; D005290:Ferric Compounds / Q000737:chemistry* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008855:Microscopy, Electron, Scanning; D010710:Phosphates / Q000378:metabolism*; D013056:Spectrophotometry, Ultraviolet; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000378:metabolism*; D014961:X-Ray Diffraction
chemical_list: D005290:Ferric Compounds; D010710:Phosphates; D062065:Wastewater; D014874:Water Pollutants, Chemical; C021024:ferric hydroxide