title: Evaluation of gas chromatography-mass spectrometry in conjunction with chemometric resolution for identification of nitrogen compounds in crude oil.
abstract: A chemometric resolution method is described for the identification of nitrogen compounds in crude oil. Prefractionation of crude oil into discrete chemical classes was performed by adsorption column chromatography using small quantities of neutral aluminum oxide and silicic acid. Subsequent high-resolution separation of individual components was achieved by using capillary column gas chromatography, and compound types were detected by mass spectrometer. In conjunction with a combined chemometric method, each principal chemical class was further resolved and separated, which made it possible to identify some nitrogen compounds in the investigated oils. To a certain extent, this method could relieve classical analysis of difficulty in identifying those species with poorly low contents or partially chromatographic overlaps, particularly in the cases where authentic standards were not available for addition into the unknown analytical systems to reveal what indeed existed in them.
authors.affiliation: College of Chemistry and Chemical Engineering, Institute of Chemometrics and Intelligent Analytical Instruments, Central South University, Changsha 410083, China.
authors.forename: Bo-Yan
authors.initials: BY
authors.lastname: Li
authors.forename: Yi-Zeng
authors.initials: YZ
authors.lastname: Liang
authors.forename: Yun
authors.initials: Y
authors.lastname: Hu
authors.forename: Yi-Ping
authors.initials: YP
authors.lastname: Du
authors.forename: You-Qun
authors.initials: YQ
authors.lastname: Song
authors.forename: Hui
authors.initials: H
authors.lastname: Cui