Optimization of the pre-process for the national standard of detection method for tetraethyl lead in workplace air

  Objective  To optimize the pretreatment process of the national standard method of solvent desorption-micro acid digestion graphite furnace atomic absorption spectrophotometry for the determination of tetraethyl lead in workplace air.

  Methods  A new tetraethyl lead desorption reagent was used, and the digestion time was adjusted. The detection limit, recovery rate, and relative standard deviation of tetraethyl lead in workplace air after pretreatment optimization were calculated through experiments and compared with national standard methods.

  Results  n-Hexane was selected as the desorption reagent in the pretreatment process, and 10 μL concentrated nitric acid was used for digestion for 60 min. After pretreatment optimization, the detection limit was 0.001 3 μg/mL with an average recovery rate of 98.3% and an average relative standard deviation of 2.7%, which met the relevant requirements of laboratory quality control specifications. Compared with the national standard method, the optimized method used less concentrated nitric acid, had a lower experimental blank, and had a higher recovery rate.

  Conclusions  The improved method was more convenient to operate, had a low reagent blank value, good result repeatability, and a high sample recovery rate.