Chemical characterization of asphaltenes from various crude oils

Leyva, Carolina; Ancheyta, Jorge; Berrueco, C.; Millán, Marcos

doi:10.1016/j.fuproc.2012.10.009

Cited by 60 publications

(38 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Furthermore, heavy crude oils may contain complex compounds like wax and asphaltene with high molecular weights . Asphaltene is defined as the heavy fraction of the crude oil which is not soluble in normal alkanes (such as n ‐heptane, n ‐hexane, and n ‐pentane) but is soluble in aromatic solvents (such as toluene and benzene) . Asphaltene is made up of polar aromatic compounds with high molecular weight, which is partly dispersed and partly dissolved in crude oil .…”

Section: Introductionmentioning

confidence: 99%

“…[4] Asphaltene is defined as the heavy fraction of the crude oil which is not soluble in normal alkanes (such as n-heptane, n-hexane, and n-pentane) but is soluble in aromatic solvents (such as toluene and benzene). [3,[5][6][7] Asphaltene is made up of polar aromatic compounds with high molecular weight, which is partly dispersed and partly dissolved in crude oil. [3,[6][7][8] Crude oil also has non-polar resins, which surround asphaltene molecules and do not let them aggregate.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Effect of ultrasonic irradiation treatment on rheological behaviour of extra heavy crude oil: A solution method for transportation improvement

et al. 2016

View full text Add to dashboard Cite

The highly viscous property of heavy oil often causes problems in its transportation in pipelines. Mixing heavy oil with light oil as well as ultrasound treatment are viable solutions to this problem. In this study, extra heavy crude oil samples were first diluted with 0, 0.05, 0.1, and 0.15 mL/mL (0, 5, 10, and 15 vol%) of a light crude oil; then the mixture was irradiated by ultrasonic waves for 0, 5, 10, 15, and 20 min; finally the viscous shear functions of all mixtures was measured at different values of shear rate at different temperature levels. The results revealed that the minimum viscosity of the diluted extra heavy crude oil samples was obtained at 10 min of ultrasonic irradiation. Moreover, the viscosity reduction rate in relation to temperature decreases as temperature increases. In other words, the maximum viscosity reduction rate occurred at 0.05 mL/mL (5 vol%) of light crude oil. Using the experimental data, the parameters of common rheological models were obtained and a new modified Power Law model was presented to calculate the effect of shear rate and temperature simultaneously.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Effect of ultrasonic irradiation treatment on rheological behaviour of extra heavy crude oil: A solution method for transportation improvement

et al. 2016

View full text Add to dashboard Cite

show abstract

“…The amount and length of the alkyl side chains as well as the number of aromatic rings may change in such a way that the variations of molecular weight and aromaticity factor of asphaltenes are notorious [14].…”

Section: Types Of Characterizations For Crude Oil and Asphaltenesmentioning

confidence: 99%

Characterization of Crude Oils and the Precipitated Asphaltenes Fraction using UV Spectroscopy, Dynamic Light Scattering and Microscopy

Cruz¹,

Rivas²,

García³

et al. 2018

Recent Insights in Petroleum Science and Engineering

View full text Add to dashboard Cite

Analysis of crude oil composition provides important information that impacts on the recovery, handling, and transportation of hydrocarbons. Crude characterization also provides data in the analysis of geochemistry of the source of origin. Crude oil characterization by optical methods is usually diicult because of its dark color; however, those characterizations are crucial because they give information that can afect some analysis procedures. Ultraviolet-visible (UV-vis) spectroscopy is a simple and practical technique that allows the characterization of crude oil through dilution in solvents. A comparative study of crude oil solutions contrasted with their asphaltene fractions was performed. Each solution was analyzed in triplicate, on a UV-vis spectrophotometer. Calibration curves for both raw solutions showed no signiicant variations, indicating stability. Additionally, the results of dispersion and migration phenomena indicated stability only for crude oil solutions. The aggregate size dispersion was diferent for each type of crude and varied with respect to time. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed the type of morphology present for each type of asphaltene.

show abstract

“…IP do petróleo P01, em relação ao P02, corrobora que este último seria mais susceptível à precipitação; além disso, os asfaltenos C7I do P02 apresentam menor razão H/C, concordando que seriam mais aromáticos e propensos à precipitação. [33][34][35] Em relação aos heteroátomos (N, O e S), pesquisas indicam que estão concentrados nos asfaltenos e desempenham papel importante na autoassociação, pois normalmente fazem parte de suas porções polares, sítios em que ocorreriam ligações de hidrogênio e transferência de carga, interações envolvidas no processo de precipitação. 2,36 Neste trabalho foram avaliados os percentuais de oxigênio (O) e nitrogênio (N): ambos foram sempre maiores nos asfaltenos em relação aos maltenos correspondentes, concordando com resultados encontrados na literatura.…”

Section: Composição Elementar (Chno) Dos Petróleos E Frações C5 E C7 unclassified

Avaliação De Asfaltenos Precipitados Em Diferentes Condições De Composição, Temperatura E Pressão

Moura¹,

Rosa²

2017

Quim. Nova

View full text Add to dashboard Cite

EVALUATION OF ASPHALTENE PRECIPITATION IN DIFFERENT CONDITIONS OF COMPOSITION, TEMPERATURE, AND PRESSION.Asphaltenes are a heavy fraction of petroleum with the ability for self-association, a phenomenon that can occur spontaneously in the reservoirs or in any of the various stages of production and processing, depending on variations in pressure, temperature, composition and shearing, among others. In this work, it was evaluated the precipitation of asphaltenes in two oils (P01 and P02) in different conditions of temperature and pressure and in the absence or presence of CO 2 . Under high pressure and temperature conditions, the precipitation of asphaltenes was observed in the presence of CO 2 in mixtures with methane, while the addition of propane induced precipitation in the absence of CO 2 . The results of analyses elemental (CHNO), SEM, FTIR and LDI-MS were consistent with the structure assigned to samples of this nature (oils, maltenes and fractions of asphaltenes insoluble in n-pentane, C5I, and n-heptane, C7I).Keywords: asphaltenes; precipitation; characterization; carbon dioxide; light alkanes. INTRODUÇÃOO petróleo é uma mistura complexa constituída de hidrocarbonetos saturados, aromáticos, resinas e asfaltenos.1,2 O sistema polidisperso formado pelo petróleo normalmente está em condições de equilíbrio, mas perturbações como variações de composição, temperatura e pressão, podem induzir a precipitação dos asfaltenos. 2,3Outros fatores como cisalhamento e efeitos eletrocinéticos aparentemente também exercem este efeito. 1,4,5 Estudos indicam que a precipitação de asfaltenos também pode ocorrer espontaneamente nos reservatórios, levando à formação de nanopartículas, principalmente quando essa fração está presente em baixas concentrações (< 0,1 g L -1).6-8 Esse fenômeno, no entanto, normalmente está relacionado à produção/recuperação do petróleo, principalmente devido a variações de temperatura e à despressurização, comum nesses processos.9-12 Na prática, uma das razões mais frequentes para a ocorrência desse fenômeno in situ é a injeção de gases (CO 2 , N 2 , hidrocarbonetos leves, gás natural) nos processos de recuperação avançada, ou métodos especiais de recuperação do petróleo. 10,[13][14][15][16] Nos petróleos brasileiros são pouco comuns problemas de precipitação de asfaltenos, mas estudos indicam que este fenômeno deve ocorrer nos campos do pré-sal, devido à injeção de CO 2 prevista para esses poços.12,17,16 Além de ser um fluido de injeção nos processos de recuperação, o CO 2 é um dos constituintes do gás natural e do próprio petróleo, geralmente presente em concentrações entre traços e 5% (em mol), 18 podendo, contudo, chegar a concentrações mais elevadas, como cerca de 20% (em volume) nos reservatórios do pré-sal. 19Em alguns processos de recuperação do petróleo, a precipitação dos asfaltenos é desejada, como no VAPEX, um dos processos baseados no uso de solventes no qual propano (puro ou como componente majoritário de uma mistura de hidrocarbonetos leves) é injetado em reservatórios para a diluiçã...

show abstract

Chemical characterization of asphaltenes from various crude oils

Cited by 60 publications

References 17 publications

Effect of ultrasonic irradiation treatment on rheological behaviour of extra heavy crude oil: A solution method for transportation improvement

Effect of ultrasonic irradiation treatment on rheological behaviour of extra heavy crude oil: A solution method for transportation improvement

Characterization of Crude Oils and the Precipitated Asphaltenes Fraction using UV Spectroscopy, Dynamic Light Scattering and Microscopy

Avaliação De Asfaltenos Precipitados Em Diferentes Condições De Composição, Temperatura E Pressão

Contact Info

Product

Resources

About

Chemical characterization of asphaltenes from various crude oils

Cited by 60 publications

References 17 publications

Effect ­­­­­of ultrasonic irradiation treatment on rheological behaviour of extra heavy crude oil: A solution method for transportation improvement

Effect ­­­­­of ultrasonic irradiation treatment on rheological behaviour of extra heavy crude oil: A solution method for transportation improvement

Characterization of Crude Oils and the Precipitated Asphaltenes Fraction using UV Spectroscopy, Dynamic Light Scattering and Microscopy

Avaliação De Asfaltenos Precipitados Em Diferentes Condições De Composição, Temperatura E Pressão

Contact Info

Product

Resources

About

Effect of ultrasonic irradiation treatment on rheological behaviour of extra heavy crude oil: A solution method for transportation improvement

Effect of ultrasonic irradiation treatment on rheological behaviour of extra heavy crude oil: A solution method for transportation improvement