Highly sensitive determination of antimony and selenium in crude oils by oxygen-bomb combustion ICP-MS

It is important to determine trace amounts of antimony and selenium in crude oil, since they are known to be catalyst poisons in the refinery processes. The decomposition of crude oil by an oxygen-bomb combustion method was studied in order to determine antimony and selenium by ICP-MS. By a decomposition procedure, organic antimonious and selenious compounds were completely converted into the corresponding inorganic species, which were absorbed by a 0.01 M nitric acid and 1% hydrogen peroxide solution. The detection limit of the proposed method was 1 ng g(-1) for both elements. This method was applied to the determination of trace amounts of antimony and selenium in various crude oils.