Analysis of Metals in Petroleum Cuts

The petroleum industry faces the need to analyze numerous elements which are either naturally present in crude oil as is particularly the case for nickel and vanadium or those elements that are added to petroleum products during refining. 

In this section we will discuss only the analytical techniques that are in very general usage without presenting the older chemical methods. 

The method has been described previously. The metals most frequently analyzed are the following  

The detectable limits for a dispersion apparatus are a few g-g/g, and vary according to the environment around from a few pg/g for heavy elements in light matrices to a few mg/g for light elements. 

The sample to be analyzed can be dissolved in an organic solvent, xylene or methylisobutyl ketone. Generally, for reasons of reproducibility and because of matrix effects (the surroundings affect the droplet size and therefore the effectiveness of the nebulization process), it is preferable to mineralize the sample in H2SO4, evaporate it and conduct the test in an aqueous environment. 

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