title: Removal of heavy metal ions by iron oxide coated sewage sludge.
abstract: The municipal sewage sludge was modified with iron oxide employed in metal ions removal. The surface modification method was proposed and the effect of parameters in the preparation was studied. The iron oxide coated sludge had higher surface area, pore volume and iron content, compared to uncoated sludge. The suitable conditions for removal of Cu(II), Cd(II), Ni(II) and Pb(II) ions from solutions were investigated using batch method. The suitable pH value in the extraction was 7 for adsorption of Cd(II) and Ni(II), 6 for Cu(II) and 5 for Pb(II) ions. The presence of NaNO(3), Ca(NO(3))(2) and Na(2)SO(4) in metal solution in the concentration of 0.01 M and 0.50 M could reduce the removal efficiency. The adsorption isotherms for the adsorption of the metal ions were defined by Langmuir relation. The maximum adsorption capacity of the iron oxide coated sludge for Cu(II), Cd(II), Ni(II) and Pb(II) was 17.3, 14.7, 7.8 and 42.4 mg g(-1), respectively. The adsorption kinetics for every metal ions followed pseudo-second order model. The metal removal from wastewater by iron oxide coated sludge was also demonstrated.
authors.affiliation: Inter-Department of Environmental Science, Chulalongkorn University, Bangkok, Thailand.
authors.forename: Thapanapong
authors.initials: T
authors.lastname: Phuengprasop
authors.forename: Jarinya
authors.initials: J
authors.lastname: Sittiwong
authors.forename: Fuangfa
authors.initials: F
authors.lastname: Unob
mesh_terms: D000327:Adsorption; D005290:Ferric Compounds / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D019216:Metals, Heavy / Q000302:isolation & purification*; D012722:Sewage; D013816:Thermodynamics
chemical_list: D005290:Ferric Compounds; D019216:Metals, Heavy; D012722:Sewage; C000499:ferric oxide