USGS Method I-1232:Chromium, hexavalent, dissolved, water, FLAA
|Brief Method Summary:||Hexavalent chromium is determined by atomic absorption spectrometry. The element is chelated with ammonium pyrrolidine dithio-carbamate (APDC) and extracted with methyl isobutyl ketone (MIBK). The extract is aspirated into the air-acetylene flame of the spectrometer (Midgett and Fishman, 1967).|
|Scope And Application:||This method may be used to analyze water and brines containing from 1 to 25 ug/L of chromium. Samples containing more than 25 ug/L need to be diluted prior to chelation-extraction.|
If the iron concentration of the sample exceeds 5,000 ug/L, determine hexavalent chromium by the colorimetric diphenylcarbazide method (I-1230).
|Applicable Conc Range:||1- 25 ug/L|