Pyrolysis applied to the study of a Maya asphaltene

Douda, J.; Llanos, M. E.; Alvarez, Regina; Franco, Carlos López; Montoya, J.A.

doi:10.1016/j.jaap.2003.08.011

Cited by 40 publications

(47 citation statements)

References 27 publications

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“…In the present study, the whole asphaltenes were compared to their solubility fractions distinctly differing in compositional space [50], which are, in particular, the acetone-soluble fraction, the heptane/toluenesoluble (Hep/Tol) fraction, and the tetrahydrofuran/toluene/methanol-soluble (THF/Tol/MeOH) fraction. Table 1 presents the total recovery of the fractionation procedure, as well as the weight-% of the *values taken from Chacón-Patiño et al [50] The pyrolysis of asphaltenes was applied for decades to investigate their structural building blocks and to reduce their chemical complexity hardly accessible comprehensively by any analytical technique [11,32,36,37,39,55]. Figure 1 depicts the three main pathways asphaltenes undergo during evolved gas analysis: (1) Low-molecular weight compounds, typically present in the maltene fraction, were shown to evaporate intact [33].…”

Section: Resultsmentioning

confidence: 99%

Investigation of Island/Single-Core- and Archipelago/Multicore-Enriched Asphaltenes and Their Solubility Fractions by Thermal Analysis Coupled with High-Resolution Fourier Transform Ion Cyclotron Resonance Mass Spectrometry

et al. 2020

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Despite extensive research, the molecular-level chemical characterization of asphaltenes, a highly aromatic solubility fraction of petroleum, remains an analytical challenge. This fraction is related to diverse problems in crude oil exploration, transportation, and refining. Two asphaltene architecture motifs are commonly discussed in the literature, "island" (single-core)-and "archipelago" (multicore)-type structures. The thermal desorption and pyrolysis behavior of island-and archipelago-enriched asphaltenes and their extrography fractions was investigated. For this purpose, the evolved chemical pattern was investigated by thermal analysis coupled with ultrahigh-resolution mass spectrometry (Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS)). Soft atmospheric pressure chemical ionization preserved the molecular information of the thermal emission profile. Time-/temperature-resolved analysis allowed the chemical characterization of the occluded material as well as of asphaltene building blocks during pyrolysis. Regarding the thermogravimetric information, the island-type enriched sample (Wyoming asphaltenes) revealed a significantly higher coke residue after the pyrolysis process compared to the archipelago-type enriched sample (Athabasca asphaltenes). In contrast to whole asphaltenes, extrographic fractions revealed that occluded material evolved during the desorption phase. For the acetone fraction, this effect was the most abundant and suggests cooperative aggregation, which persists at high temperatures. Pyrolysis revealed a bimodal behavior for most of the compound classes, suggesting the presence of both architecture motifs in each asphaltene. double-bond equivalent (DBE) vs #C diagrams of the pyrolysis molecular profile revealed specific compositional trends: compounds with high DBE values and short alkylation are likely to be originated from island-type asphaltenes, whereas species with low DBE values and high carbon numbers likely derive from archipelago-type asphaltenes. In the asphaltene structural debate, thermal analysis ultrahigh-resolution mass spectrometry serves as an additional technique and supplements results obtained by other techniques, such as direct infusion approaches. Consistent results on the structural motifs are indicated by the molecular fingerprint visualized by DBE vs #C diagrams and serve as a measure for the dominance of a structural motif.

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Section: Resultsmentioning

confidence: 99%

Investigation of Island/Single-Core- and Archipelago/Multicore-Enriched Asphaltenes and Their Solubility Fractions by Thermal Analysis Coupled with High-Resolution Fourier Transform Ion Cyclotron Resonance Mass Spectrometry

et al. 2020

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“…However, above 620°C (see Figure 5), the deposits on the spent catalysts are defined as coke. 23 Subsequently, to interpret the different stages during the heating period, the derivative of the weight loss curve (DTG) obtained in the thermal burnoff in air atmosphere is also presented in Figure 6. Figure 6 shows that the weight loss process of the spent catalyst can be divided into several steps; the region from 25 to 208°C represents loss due to devolatilisation of light oil and beyond 620°C is coke.…”

Section: Resultsmentioning

confidence: 99%

Optimization of the CAPRI Process for Heavy Oil Upgrading: Effect of Hydrogen and Guard Bed

Hart

Shah

Leeke

et al. 2013

Ind. Eng. Chem. Res.

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Toe-to-heel air injection (THAI) and its catalytic version CAPRI are relatively new technologies for the recovery and upgrade of heavy oil and bitumen. The technologies combine horizontal production well, in situ combustion, and catalytic cracking to convert heavy feedstock into light oil down-hole. The deposition of asphaltenes, coke, and metals can drastically deactivate the catalyst in the CAPRI process. A fixed bed microreactor was used to experimentally simulate the conditions in the catalyst zone of the oil well of CAPRI. In this study, oil upgrading and catalyst deactivation in the CAPRI process were investigated in the temperature range of 350−425°C, pressure of 20 barg and residence time of 9.2 min. Additionally, a guard bed consisting of activated carbon particles prior to the active catalyst in a microreactor and/or the addition of hydrogen to the gas feed were used to minimize coke formation and catalyst deactivation through respectively removing and hydrocracking the coke precursors. It was found that depending on the upgrading temperature, the viscosity of the produced oil reduced significantly by 42−82% and (American Petroleum Institute) API gravity increased by ∼2 to 7°API relative to the feedstock of 0.49 Pa·s and 13°API, respectively. Conversely, the use of hydrogen further increased the API gravity by 2°API and the viscosity by 5.3%. Notably, the coke content of the catalyst reduced from 57.3 wt % in nitrogen to 34.8 wt % in hydrogen atmosphere. The use of a guard bed increased the API gravity of the produced oil by a further 2°and reduced the viscosity by an average of 8.5% further than achieved with the active HDS catalyst CoMo/alumina.

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“…In terms of thermal cracking temperature reduction of asphaltenes and the energy needed to activate the thermolysis reactions, a better performance was carried out by the NiO nanoparticles followed by Co 3 O 4 and Fe 3 O 4 [44]. Besides, the study reported that during the pyrolysis of asphaltenes, the C-S bonds are broken around 350-400 • C, while the C-C bonds require temperatures higher than 400 • C, which are relatively elevated temperatures, and for which the use of a catalyst is necessary, with which, these temperatures are reduced to approximately 250-300 • C. Asphaltenes from Maya crude oil were subjected to pyrolysis, obtaining maltenes, gases, and coke as products [141]. This is explained by the fact that heterocyclic nitrogen can play a key role in the thermal cracking reactions of asphaltenes and resins, since the first reactions involve the breaking of aromatic alkyl bonds.…”

Section: Influence Of Nanoparticles In Pyrolysis Reactionsmentioning

confidence: 99%

Nanotechnology Applied to Thermal Enhanced Oil Recovery Processes: A Review

et al. 2019

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The increasing demand for fossil fuels and the depleting of light crude oil in the next years generates the need to exploit heavy and unconventional crude oils. To face this challenge, the oil and gas industry has chosen the implementation of new technologies capable of improving the efficiency in the enhanced recovery oil (EOR) processes. In this context, the incorporation of nanotechnology through the development of nanoparticles and nanofluids to increase the productivity of heavy and extra-heavy crude oils has taken significant importance, mainly through thermal enhanced oil recovery (TEOR) processes. The main objective of this paper is to provide an overview of nanotechnology applied to oil recovery technologies with a focus on thermal methods, elaborating on the upgrading of the heavy and extra-heavy crude oils using nanomaterials from laboratory studies to field trial proposals. In detail, the introduction section contains general information about EOR processes, their weaknesses, and strengths, as well as an overview that promotes the application of nanotechnology. Besides, this review addresses the physicochemical properties of heavy and extra-heavy crude oils in Section 2. The interaction of nanoparticles with heavy fractions such as asphaltenes and resins, as well as the variables that can influence the adsorptive phenomenon are presented in detail in Section 3. This section also includes the effects of nanoparticles on the other relevant mechanisms in TEOR methods, such as viscosity changes, wettability alteration, and interfacial tension reduction. The catalytic effect influenced by the nanoparticles in the different thermal recovery processes is described in Sections 4, 5, 6, and 7. Finally, Sections 8 and 9 involve the description of an implementation plan of nanotechnology for the steam injection process, environmental impacts, and recent trends. Additionally, the review proposes critical stages in order to obtain a successful application of nanoparticles in thermal oil recovery processes.

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Pyrolysis applied to the study of a Maya asphaltene

Cited by 40 publications

References 27 publications

Investigation of Island/Single-Core- and Archipelago/Multicore-Enriched Asphaltenes and Their Solubility Fractions by Thermal Analysis Coupled with High-Resolution Fourier Transform Ion Cyclotron Resonance Mass Spectrometry

Investigation of Island/Single-Core- and Archipelago/Multicore-Enriched Asphaltenes and Their Solubility Fractions by Thermal Analysis Coupled with High-Resolution Fourier Transform Ion Cyclotron Resonance Mass Spectrometry

Optimization of the CAPRI Process for Heavy Oil Upgrading: Effect of Hydrogen and Guard Bed

Nanotechnology Applied to Thermal Enhanced Oil Recovery Processes: A Review

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