The idea of simultaneous batch in-situ extraction and arsenic and antimony hydride generation atomic absorption spectrometry determination directly in the solid (tsunami and lake sediments) samples

摘要

The article presents the application of in-situ extraction from a solid sample in order to determine metalloids: arsenic and antimony. The reaction vessel, in which hydride generation followed the extraction, was connected with the atomic absorption spectrometer (AAS) in a fast sequential mode. Deionised water, phosphatic buffer (pH = 6) and hydrochloric acid (2 molL~(-1)) were used as the extractants to determine the concentration of metalloids in the following fractions: easily (water) leachable, exchangeable, and acid teachable. Two different types of sediments were used while developing the application: lake bottom sediments and tsunami deposits. Both types of the sediments samples (5-20 mg) were placed directly in the reaction vessel and after in-situ extraction the determination of the metalloids was conducted, what allowed to assess concentration of arsenic and antimony during single analysis. The results obtained from the analyses of both sediments types were compared with the results from traditional off-line extraction. As a result a good correspondence with both hydrochloric acid and phosphatic buffer was found. The methodology of solid samples analysis was developed with detection limits of 50 ng g~(-1) (for As) and 30 ng g~(-1) (for Sb) for 10mg of a solid sample.