Determination of antimony in poly(ethylene terephthalate) by volatile bromide generation flame atomic absorption spectrometry

A chemical volatilization method has been developed for the determination of antimony in poly(ethylene terephthalate) (PET), after a simple acid digestion using discontinuous volatile generation and efficient introduction to a flame atomic absorption spectrometer (FAAS). The method has been evaluated and optimized by different approaches which included experimental design, numerical evaluation, visual interpretation of 3-D surface response, and artificial neural network. Its performance showed a detection limit (3s) of 300 ng as the absolute detection limit for a sample injection of 215 µL. The linear response, at 217.6 nm, ranged from 1.0 to 17.2 µg of Sb(V), with a reproducibility of 4.5 (% r.s.d.). The Sb content in PET analyzed by this method was found in the range 98–190 mg·kg−1, which was in good agreement with an ICP-AES standard method, and demonstrated a low level of interferences.