Abstract:
Cellulose-g-oxolane-2,5-dione nanofibers were prepared as an adsorbent for simultaneous separation and preconcentration of trace amounts of Cd, Cu, Fe, Pb and Zn ions in gasoline samples prior to ICP-OES detection. The nanofibers were chemically and morphologically characterized by FTIR, solid-state 13C NMR, BET and SEM techniques. The influences of experimental parameters such as pH, HNO3 concentration on metal ion elution from the nanofibers, flow rate and sample volume were investigated. The metal ions were retained on 0.5 g of the adsorbent at pH 6 and recovered with 5.0 mL of 2.0 mol L−1 HNO3. The adsorption capacities for the adsorbent were 273.1, 183.6, 195.5, 236.2 and 182.4 mg g−1 for Cd, Cu, Fe, Pb and Zn, respectively. The relative standard deviation was <3% (n = 15), limits of detection and quantification were 0.13–0.68 μg L−1 and 0.42–2.2 μg L−1, respectively, and the maximum preconcentration factor was 60. It was observed that cellulose-g-oxolane-2,5-dione nanofibers can be used for more than 30 adsorption–elution cycles without decreasing the extraction efficiency. The accuracy of the method was confirmed by analyzing a certified reference material and by performing the spike recovery test. The accuracy and recovery for different metal ions were in the range of 97–102% and 96–99%, respectively. The optimized method was applied for the separation and preconcentration of metal ions in gasoline samples.
