Synergistic Extraction-Atomic Spectrophotometric Determination of Vanadium in Foods and Petroleum Crudes with 5,5′-Methylenedisalicylohydroxamic Acid (MEDSHA)

Abstract A method is described for the flame atomic absorption spectrometry (AAS) determination of vanadium, down to microgram level, in food samples and petroleum crudes. The procedure is based on the synergistic extraction of the V(V)-5,5′-methylene-disalicylohydroxamic acid (MEDSHA) complex with a 0.5 M tributyl phosphate (TBP) solution in isobutyl methyl ketone (IBMK). The method is highly selective and has a detection limit of 0.019 μg.ml−1 (Vorg./Vsq. = 0.2) and of 0.006 μg.ml−1 (Vorg./Vsq. = 0.05), with a relative standard deviation (RSD) not exceeding 1.5% at a level of 2 μg.ml−1 and 3% at a level of 0.4 μg.ml−1.