Derivation of structural parameters for coal-derived oil by carbon-13 nuclear magnetic resonance spectrometry

Yoshida, Tadashi; Maekawa, Yosuke; Uchino, Hiroyuki; Yokoyama, Susumu

doi:10.1021/ac50056a011

Cited by 47 publications

(8 citation statements)

References 22 publications

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“…The assignments of the chemical shift regions for aliphatic carbons are summarised in Table 3. However, it was still difficult to resolve the broad peaks in the aromatic region (100 to 160 ppm), as both the DEPT-135 and 13 C NMR spectra suffered from the overlap of both protonated and bridgehead carbons as shown in Figures 2 and Figure 3. In literature reports, the chemical shift regions of bridgehead carbon region was assigned up to 137 ppm (Masuda et al, 1996;Michon et al, 1997;Rafenomanantsoa et al, 1994;Yoshida et al, 1980), as it was believed that hetero aromatic rings and hydroxyl group could push the chemical shift of some bridgehead carbon as far as 137 ppm in spectra. Considering the relative rarity of hetero aromatic ring in asphaltenes, the upper limit of the bridgehead carbon region was assigned to 133 ppm as suggested by Artok el al (1999) and Andrews et al (2011).…”

Section: Carbon Typesmentioning

confidence: 99%

“…Snape and Ladner (1979) compiled a survey of 13 C chemical shift in aromatic hydrocarbons in coal-derived materials. Since then a large body of literature on asphaltene molecular parameters using 13 C NMR has been reported (Artok et al, 1999;Begon et al, 2003;Buenrostro-Gonzalez et al, 2001;Calemma et al, 1995;Christopher et al, 1996;Dickinson, 1980;Fergoug and Bouhadda, 2014;Gillet et al, 1980;Korb et al, 2013;Masuda et al, 1996;Michon et al, 1997;Myhr et al, 1990;Netzel, 1987;Ostlund et al, 2004;Rafenomanantsoa et al, 1994;Sanchez-Minero et al, 2013;Sheremata et al, 2004;Storm et al, 1994;Trejo et al, 2007;Yoshida et al, 1980). Likewise, since its introduction in 1988, laser desorption ionisation mass spectrometry has been increasingly used in the study of heavy fractions of petroleum (Karas and Hillenkamp, 1988).…”

Section: Introductionmentioning

confidence: 99%

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Characterisation of subfractions of asphaltenes extracted from an oil sand using NMR, DEPT and MALDI-TOF

Zheng

Zhu

Zareie

et al. 2018

Journal of Petroleum Science and Engineering

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This paper reports the findings of an investigation into molecular structures and properties of an oil sand asphaltene sample and its subfractions. The asphaltene sample extracted from Buton Oil Sand (Indonesia) was fractionated stepwise into four subfractions by precipitation in a binary solvent system made from mixtures of dichloromethane/n-heptane with volumetric ratios of 30/70, 20/80 and 10/90, respectively. The average molecular structural parameters, including the average polycyclic aromatic hydrocarbon size, average side chain length and average molecular weight of the oil sand asphaltene sample and its subfractions, were measured and compared, using characterisation data obtained from nuclear magnetic resonance in combination with distortionless enhancement by polarisation transfer. The molecular weight distributions of the asphaltene samples were measured using a matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry. The results indicated that the island molecular architecture was featured in all the asphaltene samples. The average polycyclic aromatic hydrocarbon size was found to be 7 rings for the least soluble subfraction, 6 rings for the other subfractions and the oil sand asphaltenes. The fractionation mechanism was dictated by polarity difference amongst subfractions as a result of relative luxuriance of the aliphatic parts. The use of 13 C NMR, DEPT and MALDI-TOF was shown to provide a useful means for characterisation and estimation of molecular structures of the asphaltenes.

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Section: Carbon Typesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Characterisation of subfractions of asphaltenes extracted from an oil sand using NMR, DEPT and MALDI-TOF

Zheng

Zhu

Zareie

et al. 2018

Journal of Petroleum Science and Engineering

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“…NMR has proven to be a powerful tool in the determination of asphaltene structures, as shown in the recent review by Ok and Mal . Solution- and solid-state NMR have been used to study asphaltene structure. − Fergoug and Bouhadda studied structural parameters of the asphaltenes derived from the Algerian Hassi Messoud oilfield using 1 H and 13 C liquid NMR, finding that the PAH region contains seven fused aromatic rings (7FAR). Scotti et al concluded, from a liquid-state 1 H and 13 C NMR study, that the most probable number of fused aromatic rings in asphaltene PAHs is seven.…”

Section: Introductionmentioning

confidence: 99%

Experimental and Theoretical Approach To Determine the Average Asphaltene Structure of a Crude Oil from the Golden Lane (Faja de Oro) of Mexico

et al. 2020

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The structural parameters and average molecular structures of the asphaltenes obtained from the Aguacate oilfield, located in the Golden Lane of Mexico, have been investigated combining experimental analysis and molecular simulation. The average molecular structural parameters of the polycyclic aromatic hydrocarbon (PAH) region, average number of fused aromatic rings (nFAR), average structural isomers in the polydispersity of the PAH core, average architecture, average molecular weight, and substituents in the PAH core have been determined by means of 13 C single-pulse excitation (SPE) nuclear magnetic resonance (NMR) in combination with 13 C distortionless enhancement by polarization transfer (DEPT)-135°experiments, 1 H NMR, X-ray photoelectron spectroscopy, fluorescence emission, and matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectrometry. The total energy of the PAH isomers and their fluorescence emission are calculated with density functional theory and ZINDO/S, respectively. The PAH region structural parameters determined are (a) Y-carbons (C Y ) or internal triple bridgehead aromatic carbons, (b) external peripheral aromatic carbon atoms at the junction of two fused rings (C AP3 ), (c) aromatic carbon atoms bonded to hydrogen atoms (C AH ), (d) aromatic carbon atoms bonded to heteroatom (C AX ), (e) aromatic carbon atoms bonded to hydrogen at the β position with respect to the heteroatom (C AHβX ), and (f) substituted aromatic carbon atoms (C A-Caliph ). The 13 C NMR chemical shift ranges used for the different structural carbon atoms in the PAH core were obtained from our previous study [

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“…These are approximate methods, and their accuracy depends upon the accuracy of the data used. For example, chemical shift assignments used to denote specific carbon and hydrogen atoms vary among researchers, − where different chemical shift ranges were used to denote the same atom types. Characterizing a fuel by defining functional groups depends upon the functional groups chosen.…”

Section: Resultsmentioning

confidence: 99%

Calculation of Average Molecular Parameters, Functional Groups, and a Surrogate Molecule for Heavy Fuel Oils Using ¹H and ¹³C Nuclear Magnetic Resonance Spectroscopy

Jameel¹,

Elbaz

Emwas³

et al. 2016

Energy Fuels

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Heavy fuel oil (HFO) is primarily used as fuel in marine engines and in boilers to generate electricity. Nuclear Magnetic Resonance (NMR) is a powerful analytical tool for structure elucidation and in this study, 1 H NMR and 13 C NMR spectroscopy were used for the structural characterization of 2 HFO samples. The NMR data was combined with elemental analysis and average molecular weight to quantify average molecular parameters (AMPs), such as the number of paraffinic carbons, naphthenic carbons, aromatic hydrogens, olefinic hydrogens, etc.in the HFO samples. Recent formulae published in the literature were used for calculating various derived AMPs like aromaticity factor (݂ ), C/H ratio, average paraffinic chain length (݊), naphthenic ring number (ܴ ே ), aromatic ring number (ܴ ), total ring number (ܴ ் ), aromatic condensation index (߮) and aromatic condensation degree (Ω). These derived AMPs help in understanding the overall structure of the fuel. A total of 19 functional groups were defined to represent the HFO samples, and their respective concentrations were calculated by formulating

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Derivation of structural parameters for coal-derived oil by carbon-13 nuclear magnetic resonance spectrometry

Cited by 47 publications

References 22 publications

Characterisation of subfractions of asphaltenes extracted from an oil sand using NMR, DEPT and MALDI-TOF

Characterisation of subfractions of asphaltenes extracted from an oil sand using NMR, DEPT and MALDI-TOF

Experimental and Theoretical Approach To Determine the Average Asphaltene Structure of a Crude Oil from the Golden Lane (Faja de Oro) of Mexico

Calculation of Average Molecular Parameters, Functional Groups, and a Surrogate Molecule for Heavy Fuel Oils Using ¹H and ¹³C Nuclear Magnetic Resonance Spectroscopy

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Derivation of structural parameters for coal-derived oil by carbon-13 nuclear magnetic resonance spectrometry

Cited by 47 publications

References 22 publications

Characterisation of subfractions of asphaltenes extracted from an oil sand using NMR, DEPT and MALDI-TOF

Characterisation of subfractions of asphaltenes extracted from an oil sand using NMR, DEPT and MALDI-TOF

Experimental and Theoretical Approach To Determine the Average Asphaltene Structure of a Crude Oil from the Golden Lane (Faja de Oro) of Mexico

Calculation of Average Molecular Parameters, Functional Groups, and a Surrogate Molecule for Heavy Fuel Oils Using 1H and 13C Nuclear Magnetic Resonance Spectroscopy

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Product

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Calculation of Average Molecular Parameters, Functional Groups, and a Surrogate Molecule for Heavy Fuel Oils Using ¹H and ¹³C Nuclear Magnetic Resonance Spectroscopy