FIA - ATOMIC ABSORPTION SPECTROMETRIC DETERMINATION OF DICHROMATE ION WITH CROWN ETHERS

The connection of flame atomic absorption spectrometry directly with extractions/FIA as a complete flow system was investigated. This system was used successively in the extraction and determination of dichromate ion using different crown ethers (15C5, 18C6, DB18C6, DCH18C6 and DB24C8) and various organic solvents, viz. 1, 2-dichloroethane, chloroform, toluene, 50% toluene +50% nitrobenzene, and nitrobenzene) with injection rate 37.5 samples/hr and injection volume 80 µL. The effect of different cationic and anionic interferences that may present in the natural samples was studied. The method has acceptable precision which can be used for extraction and determination of Cr (VI) in natural samples.