Factors Affecting Ultrasonic Extraction of Lead from Laboratory-Prepared Household Paint.

摘要

In a previous National Institute of Standards and Technology (NIST) study on the reliability of ultrasonic extraction-anodic stripping voltammetry (UE/ASV) for quantitatively determining lead in paint films, it was found that the amount of lead was often considerably less than the known lead levels of the specimens. An important contributor appear to be incomplete lead solubilization during ultrasonication. This report presents the results of a follow-up study performed to examine factors affecting ultrasonic extraction of lead from laboratory-prepared paint films that had been characterized using common analytical methods. The current study had three phases. In Phase 1, five experimental variables-sonicator power, specimen mass, specimen particle size, sonication temperature, In Phase II, ultrasonic extractions, conducted under temperature and time conditions found in Phase 1 to be most effective, were performed on specimens sampled from each of the 80 NIST paint-film panels. Lead recoveries were higher than the mean recoveries reported in the previous NIST UE/ASV study for each panel. In Phase III, lead extractions from specimens sampled from a limited number of NIST paint-film panels were performed without ultrasound using a water bath with mechanical stirring of the specimens in acid solution.