Systematically structural identification of nitric compounds in crude oil with chemometric resolution

Abstract

Aimed at the problem of classification of non-hydrocarbons of crude oil, the theoretical standpoint that the polarity of a compound depends on the whole structure and composition of molecule instead of a kind of heteroatom or its functional group was presented. A method was established for the systematically structural identification of nitric compounds in crude oil. The pre-fractionation of a crude oil sample into 7 fractions was performed by diadsorption column chromatography with neutral aluminum oxide and silica gel. Subsequently, the individual components were obtained by using capillary column gas chromatography, and the types of compounds were detected by a mass spectrometer. In combination with a chemometric resolution, the compounds of fraction were further identified. This method can relieve the difficulty of classical analysis in identifying those species with very low contents or without being completely separated. The structures of 168 nitric compounds in a crude oil sample were determined by this method.

Keywords

column chromatography / chromatography-mass spectrometry / chemometric resolution / structural identification / non-hydrocarbon compound / crude oil / nitric

References

[1] LiuChang-jiu, ZhangGuang-linThe Nonhydrocarbon Compounds in Petroleum and its Products[M], 1992, Beijing, Petrochemical Industry Press

[2] LiuLuo-fu, MaoDong-feng. New methods for researching into petroleum migration[J]. Development of Geoscience, 1996, 11(6): 607-610(in Chinese)

[3] LiuLuo-fu, XuDe-xin, MaoDong-feng, et al.. Primary exploration of applying carbazole compounds in study on migrations of petroleum and natural gas[J]. Chinese Science Bulletin, 1997, 42: 420-423(in Chinese)

[4] MansfieldC T, BarmanB N, ThomasJ V, et al.. Petroleum and coal[J]. Anal Chem, 1997, 69: 59R-93R

[5] BarmanB N, CebollaV L, MembradoL. Chromatographic techniques for petroleum and related products[J]. Crit Rev Anal Chem, 2000, 30(2–3): 75-120

[6] LiYuan, KangRen-hua, LiaoYong-sheng, et al.. The synthesized chromatography separation for nitrogen-, sulphur-, oxygen-containing compounds in heavy oils[J]. Acta Sedimentologica Sinica, 2001, 19(2): 276-281(in Chinese)

[7] WalshC. Enabling the chemistry of life[J]. Nature, 2001, 409: 226-231

[8] ShenHai-lin, LiangYi-zeng, YuRu-qin, et al.. The resolution of polyring-aromatic hydrocarbons in atmospheric granules over Hong Kong by HELP method[J]. Science in China, Series B, 1997, 27(6): 556-563(in Chinese)

[9] LiangYi-zengWhite Grey and Black Multicomponent Systems and Their Chemometric Algorithms[M], 1996, Changsha, Hunan Publishing House of Science and Technology(in Chinese)

[10] QiYun-peng, SunSheng-li, WuYu-tian, et al.. Application of heuristic evolving latent projection to the determination of loureirin B in resina draconis extracted by different methods[J]. Chinese Journal of Analytical Chemistry, 2002, 30(7): 797-800(in Chinese)

[11] KvalheimO M, LiangY Z. Heuristic evolving latent projections: resolving two-way multicomponent data (I): selectivity, latent-projective graph, datascope, local rank and unique resolution[J]. Anal Chem, 1992, 64: 936-946

[12] KvalheimO M, LiangY Z. Heuristic evolving latent projections: resolving two-way multicomponent data (II). detection and resolution of minor constituents[J]. Anal Chem, 1992, 64: 946-953

[13] IvanovS, AlkaneM, KalitchinZ D. Chromatographic retention indices and their application in structural identification of organic compounds[J]. Bulgarian Chemical Communications, 1992, 25: 344-351