Flame atomic absorption spectrometric determination of silver in geological materials using a flow-injection system with on-line preconcentration by coprecipitation with diethyldithiocarbamate

✍ Scribed by Shiqiao Pei; Zhaolun Fang

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 780 KB
• Volume: 294
• Category: Article
• ISSN: 0003-2670
• DOI: 10.1016/0003-2670(94)80193-2

✦ Synopsis

Trace amounts of silver in geological samples were determined by flame atomic absorption spectrometry. The analyte was preconcentrated and separated from the bulk of the matrix by on-line coprecipitation with the iron(diethyldithiocarbamate complex in the presence of l,lO-phenanthroline in a flow-injection system. The precipitate was collected in a knotted reactor without using a filter. The precipitate was dissolved in isobutyl methyl ketone and introduced directly into the nebulixer-burner system of an atomic absorption spectrometer. l,lO-Phenanthroline was added to the sample solution to mask large concentrations of iron(I1). The tolerance of the method for iron was thus increased to 4 g I-'. An enhancement factor of 26 and a concentration efficiency of 28 ' -' were obtained for a coprecipitation time of 45 s, resulting in a sampling frequency of 62 h-l. The detection Et (3~) in the sample solution was 0.5 pg I-'. The relative standard deviation at the 30 pg 1-i level was 2.1%. The analytical results obtained for geological reference materials were in good agreement with the certified values.