The direct determination of twelve elements in tungsten products using graphite furnace atomic absorption spectrometry is presented Various sample dissoluents were examined for their dissolution speed

efficiency

background generated

blank and effect on analyte signal Except for Al

ammonium citrate in aqueous ammonium is found to be an appropriate dissoluent for all the analyte Tartaric acid in aqueous ammonia is more suitable for Al in view of those factors examined The influence of tungsten matrix was studied in detail Compared to pyrolytic graphite (PG) tube

tungsten coated pyrolytic graphite (WPG) tube can improve Al

As

Bi and Sn signals to a greater extent

and can eliminate the tungsten matrix interference Thus

analyte simple standard solution can be used for calibration The detection limits (3 σ ) for Al

As

Bi

Cd

Co

Cr

Cu

Mn

Ni

Pb

Sb and Sn are 1 43

0 65

3 69

0 06

0 32

0 40

0 64

0 10

0 38

0 38

0 43 and 1 03 μg/L respectively The feasibility of the proposed method is evaluated by analyzing WO 3 standard reference materials (BYG 1201 1￣3) and various real tungsten products The analytical results are satisfactory The relative standard deviations are within 1 2%￣5 6% and the recoveries for the real sample are within 89%￣114%