CHARACTERIZATION OF BASIC NITROGEN COMPOUNDS IN AROMATIC AND RESIN FRACTIONS IN VACCUM GAS OILS BY ION MOBILITY-TIME-OF-FLIGHT MASS SPECTROMETRY

Abstract

Abstract: Vacuum gas oil (VGO) samples were separated into saturates, aromatics and resin by column chromatography，then the basic nitrides in aromatics and resin fractions were characterized by electrospray ionization source (ESI) ion mobility-time-of-flight mass spectrometry (IMS-TOF MS), and the structural differences of the basic nitrides in VGOs from different sources were analyzed. The results showed that for VGO samples from different sources, even if the unsaturated degree of basic nitride was close, there were obvious differences in the connection mode of aromatic ring; however, for the aromatic components and resin of the same sample, the carbon number was similar, and the number of equivalent double bonds in resin was slightly lower. Taking the heteronuclear single quantum coherence test of NMR spectrometer and the evaluation of hydrodenitrogenation reaction as the auxiliary evidence, the relationship between the side chain length of aromatic ring of basic nitride in VGO and its removal difficulty was further speculated. Combining column chromatography with ESI IMS-TOF MS can solve the problem that samples with high wax content are difficult to dissolve, and weaken the ionization inhibition of strong polar components, thus obtaining more comprehensive mass spectrum information than direct injection.

Key words: vacuum gas oil, nitrogen compounds, ion mobility, TOF mass spectrometry, column chromatography, NMR

CLC Number:

References

[1]Mills G A， Boedeker E R， Oblad A G.Chemical Characterization of CatalystsI. Poisoning of Cracking Catalysts by Nitrogen Compounds and Potassium Ion[J].Journal of the American Chemical Society, 1950, 72(4):1554-1560 [2]Chen Xiaobo， Shen Benxian， Sun Jinpeng， et al.Characterization and Comparison of Nitrogen Compounds in Hydrotreated and Untreated Shale Oil by Electrospray Ionization (ESI) Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR MS)[J].Energy & Fuels, 2012, 26(3):1707-1714 [3] Chen Xiaobo， Li Teng， Xin Li， et al.Inductive effect of basic nitrogen compounds on coke formation during the catalytic cracking process[J]. Catalysis Communications，2016，74：95-98.[J].Catalysis Communications, 2016, 74(10):75-78 [4]Cerqueira H S， Caeiro G， Costa L， et al.Deactivation of FCC catalysts[J].Journal of Molecular Catalysis A：Chemical, 2008, 292(1-2):1-13 [5]Bauserman J W， Nguyen K M， Mushrush G W.Nitrogen compound determination and distribution in three source fuels by GCMS[J].Petroleum Science and Technology, 2004, 22(11-12):1491-1505 [6]Laredo G C， Leyva S， Alvarez R， et al.Nitrogen compounds characterization in atmospheric gas oil and light cycle oil from a blend of Mexican crudes[J].Fuel, 2002, 10(81):1341-1350 [7] 中国石油天然气有限公司.固相萃取柴油中含氮化合物的方法[P]. 中国：106324158A，2017-01-11. [8] 中国石油化工股份有限公司.固相萃取分离原油或重油中不同类型化合物的方法[P]. 中国：106947515A，2017-07-14. [9]史得军，陈菲，梁迎春，等.固相萃取气相色谱-质谱分析催化裂化柴油中的含氮化合物[J].分析测试学报, 2018, 37(12):1490-1494 [10]Zhu Xiaochun， Shi Quan， Zhang Yahe， et al.Characterization of Nitrogen Compounds in Coker Heavy Gas Oil and Its Subfractions by Liquid Chromatographic Separation Followed by Fourier Transform Ion Cyclotron Resonance Mass Spectrometry[J].Energy & Fuels, 2011, 25(1):281-287 [11]Shi Quan， Xu Chunming， Zhao Suoqi， et al.Characterization of Basic Nitrogen Species in Coker Gas Oils by Positive-Ion Electrospray Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry[J].Energy& Fuels，2010，24：563-569., 2010, 24:563-569 [12] 陈小博，沈本贤，孙金鹏，等.焦化蜡油中碱性氮化合物的ESI FT-ICR MS表征及其催化裂化反应特性[J].石油炼制与化工, 2013, 44(7):22-27 [13]Kanu A B， Dwivedi P， Tam M， et al.Ion mobility-mass spectrometry[J].J Mass Spectrom, 2008, 43(1):1-22 [14]Fernandez-Lima F A， Becker C， Mckenna A M， et al.Petroleum Crude Oil Characterization by IMS-MS and FT-ICR MS[J].Analytical Chemistry, 2009, 81(24):9941-9947 [15]Parulkar A， Thompson J A， Hurt M， et al.Improving Hydrodenitrogenation Catalyst Performance through Analyzing Hydrotreated Vacuum Gas Oil Using Ion Mobility-Mass Spectrometry[J].Industrial & Engineering Chemistry Research, 2018, 57(27):8845-8854 [16]Fasciotti M， Lalli P M， Klitzke C F， et al.Petroleomics by Traveling Wave Ion Mobility–Mass Spectrometry Using CO2 as a Drift Gas[J].Energy & Fuels, 2013, 27(12):7277-7286 [17] 吴梅，刘泽龙，田松柏，等.固相萃取/气相色谱法测定宽馏分混合油样中柴油馏分的饱和烃和芳烃含量[J].石油炼制与化工, 2006, 37(7):58-61 [18]Cho Y， Na J-G， Nho N-S， et al.Application of Saturates， Aromatics， Resins， and Asphaltenes Crude Oil Fractionation for Detailed Chemical Characterization of Heavy Crude Oils by Fourier Transform Ion Cyclotron Resonance Mass Spectrometry Equipped with Atmospheric Pressure Photoionization[J].Energy & Fuels, 2012, 26(5):2558-2565