title: Simultaneous preconcentration of cadmium and lead in water samples with silica gel and determination by flame atomic absorption spectrometry.
abstract: A new method that utilizes pretreated silica gel as an adsorbent has been developed for simultaneous preconcentration of trace Cd(II) and Pb(II) prior to the measurement by flame atomic absorption spectrometry. The effects of pH, the shaking time, the elution condition and the coexisting ions on the separation/preconcentration conditions of analytes were investigated. Under optimized conditions, the static adsorption capacity of Cd(II) and Pb(II) were 45.5 and 27.1mg/g, the relative standard deviations were 3.2% and 1.7% (for n = 11), and the limits of detection obtained were 4.25 and 0.60 ng/mL, respectively. The method was validated by analyzing the certified reference materials GBW 07304a (stream sediment) and successfully applied to the analysis of various treated wastewater samples with satisfactory results.
authors: College of Chemical Engineering, University of Science and Technology Liaoning, Anshan 114051, China.   anshanxuhb@163.com
authors: Hongbo
authors: H
authors: Xu
authors: College of Chemical Engineering, University of Science and Technology Liaoning, Anshan 114051, China.
authors: Yun
authors: Y
authors: Wu
authors: College of Chemical Engineering, University of Science and Technology Liaoning, Anshan 114051, China.
authors: Jian
authors: J
authors: Wang
authors: College of Chemical Engineering, University of Science and Technology Liaoning, Anshan 114051, China.
authors: Xuewei
authors: X
authors: Shang
authors: College of Chemical Engineering, University of Science and Technology Liaoning, Anshan 114051, China.
authors: Xiaojun
authors: X
authors: Jiang
mesh_terms: D065966:Absorption, Physicochemical; D000327:Adsorption; D002104:Cadmium / Q000032:analysis* / Q000302:isolation & purification; D006863:Hydrogen-Ion Concentration; D007477:Ions; D007854:Lead / Q000032:analysis* / Q000302:isolation & purification; D057230:Limit of Detection; D012015:Reference Standards; D058428:Silica Gel / Q000737:chemistry*; D012996:Solutions; D013054:Spectrophotometry, Atomic / Q000379:methods*; D013997:Time Factors; D014867:Water / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000302:isolation & purification
chemical_list: D007477:Ions; D012996:Solutions; D014874:Water Pollutants, Chemical; D002104:Cadmium; D014867:Water; D007854:Lead; D058428:Silica Gel
keywords: cadmium; flame atomic absorption spectrometry (FAAS); lead; preconcentration; silica gel