DIRECT DETERMINATION OF ACID DISTRIBUTIONS IN CRUDES AND CRUDE FRACTIONS

摘要

A method for the direct determination of the acid distribution in petroleum crudeoil and crude oil fractions by chlorine negative ion chemical ionization massspectrometry is disclosed. The crude oil or crude oil fraction is introducedinto a mass spectrometer followed by the introduction of a chlorinated reagentcapable of producing chloride anions that can react with the acid compounds ofthe crude oil or crude oil fractions. The mass spectrometer is operated in negativeion mode to selectively detect negatively charged chlorinated adduct ion species.Mass spectra, such as represeted on Figure 3A, are obtained, from which adductions are selected. Peaks from resulting mass sub-spectra are identifed, fromwhich the acid species are quantified, as demonstrated in Figure 3B.