Determination of iron,nickel and copper in gasoline by flame atomic absorption spectrometry

The gasoline sample was oxidized using iodine-xylene.After extraction with nitric acid(9+1),iron,nickel and copper in gasoline were determined by atomic absorption spectrometry.The wavelengths of determining iron,nickel and copper were 248.3 nm,232.0 nm and 324.8 nm,respectively.The detection limits were 0.000 5 μg/mL,0.000 4 μg/mL and 0.000 1 μg/mL,and the linear ranges were 0.002-40.00 μg/mL,0.001-50.00 μg/mL,0.000 1-6.00 μg/mL,respectively.The test for the concentration and dosage of oxidizer and extractant were carried out and the optimal extraction time was selected.The other elements in gasoline were all in tolerable amount ranges.The method has been applied for the determination of iron,nickel and copper with the relative standard deviations of less than 2.92%,2.94%,3.18% respectively,and the recovery of 98.5%-102.5%.