Petroleomics of Colombian asphaltenes: high resolution mass spectrometry view of asphaltene adsorption, reactivity, occlusion and aggregation

Los asfaltenos son considerados los componentes de menor valor agregado del petróleo, debido a que son los responsables directos de una serie de problemas operacionales a lo largo de toda la cadena de producción del crudo. Cambios mínimos en la composición química de la matriz petroquímica, así como...

Full description

Autores:
Chacón Patiño, Martha Liliana
Tipo de recurso:
http://purl.org/coar/version/c_b1a7d7d4d402bcce
Fecha de publicación:
2016
Institución:
Universidad Industrial de Santander
Repositorio:
Repositorio UIS
Idioma:
spa
OAI Identifier:
oai:noesis.uis.edu.co:20.500.14071/35548
Acceso en línea:
https://noesis.uis.edu.co/handle/20.500.14071/35548
https://noesis.uis.edu.co
Palabra clave:
Asfaltenos
Espectrometría De Masas
Agregación
Asphaltenes are considered the least valuable components of crude oil because they are responsible for serious problems during production
transporting
and upgrading. Changes in petroleum composition or physical conditions like pressure or temperature dropping
can produce asphaltene deposits
causing formation damage
pipeline plugging
and catalysts poisoning. In this sense
understanding the role of molecular composition in asphaltene behavior is fundamental to improve production and processing of petroleum. Three Colombian asphaltene samples (ASTM D6560-12) were purified via four cycles of successive maceration−Soxhlet extraction with n-heptane to extract occluded hydrocarbons. The purified asphaltene sample was then fractionated according to the degree of adsorption on SiO2 particles
by elution with n-hexane
toluene
and dichloromethane-methanol. Molecular characterization of the samples was performed on a FT-ICR mass spectrometer (15 T) using an APPI source
and the aggregation kinetics was followed using Turbiscan Lab. Fractionation of purified asphaltenes yielded three individual fractions
with different adsorption behaviors on the SiO2 surface. We observed strong correlations between asphaltene adsorption on SiO2 and molecular features such as aromaticity
heteroatom/C ratios
and degree of alkylation. We have experimental evidence suggesting that a synergy between aromaticity
steric hindrance
and heteroatom content are crucial factors in asphaltene adsorption on mineral surfaces. We also found a direct relationship between adsorption degree on the SiO2 surface and the fractions aggregation behavior in solution phase. These results suggest that π-stacking is not the only driving force in asphaltene aggregation; we found that polar interactions such as hydrogen bonding
and acid-base associations play important roles in aggregation.
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License
Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)