title: Arsenic (III,V) removal from aqueous solution by ultrafine α-Fe2O3 nanoparticles synthesized from solvent thermal method.
abstract: Ultrafine iron oxide (α-Fe(2)O(3)) nanoparticles were synthesized by a solvent thermal process and used to remove arsenic ions from both lab-prepared and natural water samples. The α-Fe(2)O(3) nanoparticles assumed a near-sphere shape with an average size of about 5 nm. They aggregated into a highly porous structure with a high specific surface area of ∼ 162 m(2)/g, while their surface was covered by high-affinity hydroxyl groups. The arsenic adsorption experiment results demonstrated that they were effective, especially at low equilibrium arsenic concentrations, in removing both As(III) and As(V) from lab-prepared and natural water samples. Near the neutral pH, the adsorption capacities of the α-Fe(2)O(3) nanoparticles on As(III) and As(V) from lab-prepared samples were found to be no less than 95 mg/g and 47 mg/g, respectively. In the presence of most competing ions, these α-Fe(2)O(3) nanoparticles maintained their arsenic adsorption capacity even at very high competing anion concentrations. Without the pre-oxidation and/or the pH adjustment, these α-Fe(2)O(3) nanoparticles effectively removed both As(III) and As(V) from a contaminated natural lake water sample to meet the USEPA drinking water standard for arsenic.
authors.affiliation: Materials Center for Water Purification, Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, 110016, PR China.
authors.forename: Wenshu
authors.initials: W
authors.lastname: Tang
authors.forename: Qi
authors.initials: Q
authors.lastname: Li
authors.forename: Shian
authors.initials: S
authors.lastname: Gao
authors.forename: Jian Ku
authors.initials: JK
authors.lastname: Shang
mesh_terms: D000327:Adsorption; D001151:Arsenic / Q000302:isolation & purification*; D018360:Crystallography, X-Ray; D007700:Kinetics; D053768:Metal Nanoparticles; D046529:Microscopy, Electron, Transmission; D012997:Solvents / Q000737:chemistry*; D013499:Surface Properties; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*
chemical_list: D012997:Solvents; D014874:Water Pollutants, Chemical; D001151:Arsenic