title: Determination of trace amounts of zinc by flame atomic absorption spectrometry after preconcentration with modified clinoptilolite zeolite.
abstract: Natural clinoptilolite was used as a sorbent material for solid-phase extraction and preconcentration of zinc. Clinoptilolite was first saturated with cadmium (II) and then modified with benzyldimethyltetradecylammonium chloride for increasing adsorption of 3-(2-arsenophenylazo)-4,5-dihydroxy-2,7-naphthalene disulfonic acid (neothorin). Zinc was quantitatively retained on the adsorbent by the column method in the pH range of 3.8-4.2 at a flow rate of 1 mL/min. It was eluted from the column with 5.0 mL 2 M nitric acid solution at a flow rate of 1 mL/min and determined by flame atomic absorption spectrometry at 213.9 nm. Zinc could be concentrated from a 0.03 microg/L solution with a preconcentration factor of 170. Relative standard deviation for 8 replicate determinations of 2.5 microg zinc in the final solution was 0.92%. The interference of a large number of anions and cations was studied in detail to optimize the conditions, and the method was successfully applied for determination of zinc in standard and real water samples.
authors.affiliation: Shahid Bahonar University of Kerman, Department of Chemistry, Kerman 76175-133, Iran. s_hajialigol@yahoo.com
authors.forename: Saeed
authors.initials: S
authors.lastname: Hajialigol
authors.forename: Mohammad Ali
authors.initials: MA
authors.lastname: Taher
authors.forename: Akbar
authors.initials: A
authors.lastname: Malekpour
mesh_terms: D000327:Adsorption; D000818:Animals; D001152:Arsenicals / Q000737:chemistry; D001391:Azo Compounds / Q000737:chemistry; D049872:Bivalvia / Q000737:chemistry; D002138:Calibration; D002708:Chlorella / Q000737:chemistry; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D010944:Plants / Q000737:chemistry; D012015:Reference Standards; D015203:Reproducibility of Results; D013054:Spectrophotometry, Atomic; D001335:Vehicle Emissions / Q000032:analysis; D014881:Water Supply / Q000032:analysis; D017641:Zeolites / Q000737:chemistry*; D015032:Zinc / Q000032:analysis*
chemical_list: C534149:3-(2,6-dibromo-4-sulfophenylazo)-6-(2-arsenophenylazo)-4,5-dihydroxynaphthalene-2,7-disulfonic acid; D001152:Arsenicals; D001391:Azo Compounds; D007202:Indicators and Reagents; D001335:Vehicle Emissions; C083175:clinoptilolite; D017641:Zeolites; D015032:Zinc