title: Defluoridation from aqueous solutions by granular ferric hydroxide (GFH).
abstract: This research was undertaken to evaluate the feasibility of granular ferric hydroxide (GFH) for fluoride removal from aqueous solutions. Batch experiments were performed to study the influence of various experimental parameters such as contact time (1 min-24h), initial fluoride concentration (1-100 mgL(-1)), temperature (10 and 25 degrees C), pH (3-12) and the presence of competing anions on the adsorption of fluoride on GFH. Kinetic data revealed that the uptake rate of fluoride was rapid in the beginning and 95% adsorption was completed within 10 min and equilibrium was achieved within 60 min. The sorption process was well explained with pseudo-first-order and pore diffusion models. The maximum adsorption capacity of GFH for fluoride removal was 7.0 mgg(-1). The adsorption was found to be an endothermic process and data conform to Langmuir model. The optimum fluoride removal was observed between pH ranges of 4-8. The fluoride adsorption was decreased in the presence of phosphate followed by carbonate and sulphate. Results from this study demonstrated potential utility of GFH that could be developed into a viable technology for fluoride removal from drinking water.
authors.affiliation: Department of Environmental Engineering, Baekun Hall #332, Yonsei University, 234 Maeji Heungeop, Wonju, 220-710 Gangwon-do, South Korea.
authors.forename: Eva
authors.initials: E
authors.lastname: Kumar
authors.forename: Amit
authors.initials: A
authors.lastname: Bhatnagar
authors.forename: Minkyu
authors.initials: M
authors.lastname: Ji
authors.forename: Woosik
authors.initials: W
authors.lastname: Jung
authors.forename: Sang-Hun
authors.initials: SH
authors.lastname: Lee
authors.forename: Sun-Joon
authors.initials: SJ
authors.lastname: Kim
authors.forename: Giehyeon
authors.initials: G
authors.lastname: Lee
authors.forename: Hocheol
authors.initials: H
authors.lastname: Song
authors.forename: Jae-Young
authors.initials: JY
authors.lastname: Choi
authors.forename: Jung-Seok
authors.initials: JS
authors.lastname: Yang
authors.forename: Byong-Hun
authors.initials: BH
authors.lastname: Jeon
mesh_terms: D005290:Ferric Compounds / Q000737:chemistry*; D005459:Fluorides / Q000737:chemistry*; D007700:Kinetics; D008956:Models, Chemical; D018508:Water Purification / Q000379:methods*
chemical_list: D005290:Ferric Compounds; C021024:ferric hydroxide; D005459:Fluorides