title: New anion-exchange solid-phase extraction support used for preconcentration and determination of lead in water samples by flame atomic absorption spectrometry.
abstract: A new chelating resin was prepared by coupling Amberlite XAD-2 with Brilliant Green through an azo spacer. The resulting resin has been characterized by FTIR spectrometry, elemental analysis, and thermogravimetric analysis and studied for the preconcentration and determination of trace Pb(II) ions from solution samples. The anionic complex of Pb(II) and iodide was retained on the resin by the formation of an ion associate with Brilliant Green on Amberlite XAD-2 in weak acidic medium. The optimum pH value for sorption of the metal ion was 5.5. The sorption capacity of the functionalized resin is 53.8 mg/g. The chelating resin can be reused for 20 cycles of sorption-desorption without any significant change in sorption capacity. A recovery of 103% was obtained for the metal ion with 0.1 M EDTA as the eluting agent. Scatchard analysis revealed that the homogeneous binding sites were formed in the polymers. The resin was subjected to evaluation through batch binding and column chromatography of Pb(II). The equilibrium adsorption data of Pb(II) on modified resin were analyzed by Langmuir, Freundlich, and Temkin models. Based on equilibrium adsorption data, the Langmuir, Freundlich, and Temkin constants were determined to be 0.192, 13.189, and 3.418 at pH 5.5 and 25 degrees C. The method was applied for lead ion determination in tap water samples.
authors.affiliation: Islamic Azad University, Department of Chemistry, Central Tehran Branch, Iran. h_ahmadpanahi@iauctb.ac.ir
authors.forename: Homayon Ahmad
authors.initials: HA
authors.lastname: Panahi
authors.forename: Ali Reza
authors.initials: AR
authors.lastname: Feizbakhsh
authors.forename: Zahra
authors.initials: Z
authors.lastname: Tafazoli
authors.forename: Elham
authors.initials: E
authors.lastname: Moniri
authors.forename: Mahshid Nikpour
authors.initials: MN
authors.lastname: Nezhati
authors.forename: Hamid Hashemi
authors.initials: HH
authors.lastname: Moghaddam
authors.forename: Somayeh Rangbar
authors.initials: SR
authors.lastname: Kelahrodi
mesh_terms: D007854:Lead / Q000032:analysis*; D011137:Polystyrenes / Q000737:chemistry; D052616:Solid Phase Extraction / Q000379:methods*; D013054:Spectrophotometry, Atomic / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D011137:Polystyrenes; D014874:Water Pollutants, Chemical; D007854:Lead; C003771:Amberlite XAD-2 resin