[Determination of trace thallium by platform-GFAAS after preconcentration with polyurethane foam].

OBJECTIVE

To develop a method for trace thallium determination.

METHODS

Thallium (L) was oxidized to thallium (III) by bromine water and the thallium (III) was complexed to [TlCl4]- in 20 mL/100 mL HCI and absorbed by polyurethane foam. The adsorbed thallium was eluted by a boiling water bath and determined by platform-GFAAS. Tl (III) could be analyzed directly and the total Tl be analyzed after oxidation, so speciation could be achieved.

RESULTS

In the range of 5-100 ng/mL the linear equation was y = 0.013x + 0. 012 with the regression coefficient 0.996. The relative standard deviation was 4.7% for the standard solution of 5.00 ng/mL and the recoveries of water samples were in the range of 95.7%-104.5%.

CONCLUSION

The proposed method could determine trace thallium as low as 0.02 ng/mL.